Demo


Demo                                                           A. Cheney
Demo                                                          Sabre Inc.
Demo                                                         August 2008
Obsoletes: 1939, 3501, 5322

                    Mail Markup Language - Version 1.0

Status of this Memo

   This document specifies an Internet standards track protocol for the
   Internet community, and requests discussion and suggestions for
   improvements.  Please refer to the current edition of the "Internet
   Official Protocol Standards" (STD 1) for the standardization state
   and status of this protocol.

   Mail Markup Language (MML) is the intellectual property (IP) of Sabre
   Inc.  Concepts introduced by this technology and specified
   constraints as a standard are protected by provisional patent with
   intent to achieve full patent protection.  Removal or omission of
   entire features of specifically the language or its containing
   standard may represent a conflict of IP unless approval for such
   removal is granted from an authorized agent of Sabre Inc.  Changes
   and additions to the standard requirements, language, or concepts
   proposed by this document are allowed without permission.  Derivative
   works and distribution are authorized unlimited without permission.

   "By submitting this Internet-Draft, each author represents that any
   applicable patent or other IPR claims of which he or she is aware
   have been or will be disclosed, and any of which he or she becomes
   aware will be disclosed, in accordance with Section 6 of BCP 79.

   "Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF), its areas, and its working groups.  Note that
   other groups may also distribute working documents as Internet-
   Drafts.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   The list of current Internet-Drafts can be accessed at
   http://www.ietf.org/1id-abstracts.html

   The list of Internet-Draft Shadow Directories can be accessed at
   http://www.ietf.org/shadow.html"






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Abstract
   Mail Markup Language (MML) is a simple tag based markup language used
   to describe and structure data in a document intended to represent
   communication across the medium of email.  MML is written in W3C XML
   Schema language.  All MML documents are XML documents that conform to
   the MML schema.  This specification intends to replace RFC 5322.

IANA Considerations
   This specification requests the registration of a namespace and two
   MIME types.  The namespace name requested is MML.  A static URI
   pointed to the location of the mail.xsd as hosted by a standards body
   is also requested for mapping to the requested namespace name.  That
   URI would become the value of the MML:schemaLocation attribute.  The
   MIME types application/mail and text/xsl are also requested.  The
   application/mail MIME type will be used to identify a MML document
   for processing as mail over any standard mail protocol.  The text/xsl
   MIME type is requested to identify documents written in the
   Extensible Markup Language (XSL) for stylesheet processing.


































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Table of Contents

1. Introduction ....................................................   5
   1.1. Scope ......................................................   5
   1.2. Requirements ...............................................   6
   1.3. Terminology ................................................   6
2. Philosophy of Design ............................................   7
   2.1. Structure ..................................................   7
   2.2. Syntax Simplicity and Understandability ....................   8
   2.3. Semantics ..................................................   8
   2.4. Accessibility ..............................................   9
   2.5. Presentation ...............................................   9
   2.6. Security ...................................................   9
3. External Technologies ...........................................  10
   3.1. Extensible Markup Language (XML) and W3C XML Schema ........  10
   3.2. XForms .....................................................  10
   3.3. Accessible Rich Internet Applications (ARIA) ...............  10
   3.4. Resource Document Framework (RDF) ..........................  10
   3.5. Stylesheet Technologies ....................................  11
   3.6. Behaviors and Scripting ....................................  11
   3.7. Public Key Infrastructure (PKI) ............................  11
   3.8. Uniform Resource Identifier (URI) ..........................  11
   3.9. Multipurpose Internet Mail Extensions (MIME) ...............  11
4. Processor Roles .................................................  11
   4.1. Processor Requirements and Constraints .....................  12
      4.1.1. Validation ............................................  12
      4.1.2. RFC 2822/5322 Conformance .............................  12
      4.1.3. Session Separation and Presentation ...................  12
      4.1.4. Session Preservation ..................................  12
      4.1.5. Character Set .........................................  13
      4.1.6. Session Timestamp .....................................  13
      4.1.7. URI Resolution ........................................  13
      4.1.8. MIME Execution Restriction ............................  13
      4.1.9. Caching ...............................................  13
      4.1.10. Local Processing .....................................  13
      4.1.11. MIME Catalogue .......................................  14
      4.1.12. From and Reply-to Tags ...............................  14
      4.1.13. Attachments ..........................................  14
      4.1.14. Processing of <plain-text> ...........................  15
      4.1.15. Processing of style Attribute ........................  15
      4.1.16. Internationalization Attribute Processing ............  15
      4.1.17. refer Attribute Processing ...........................  15
   4.2. Processor Allowances .......................................  15
      4.2.1. Processor Default Presentation ........................  15
      4.2.2. Processor Default Behaviors ...........................  16
5. Default mime.xsd ................................................  16
6. MML Schema ......................................................  36
7. MML Schema Header Documentation .................................  50
   7.1. MIME Type Usage and mime.xsd ...............................  50
   7.2. MML Header Documentation ...................................  50
      7.2.1. Root Element ..........................................  51

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      7.2.2. <session> Tag .........................................  51
      7.2.3. <address> Tag .........................................  51
      7.2.4. <to>, <copy>, <blind-copy>, and <from> Tags ...........  52
      7.2.5. <agent> Tag ...........................................  52
      7.2.6. <mail-address> Tag ....................................  52
      7.2.7. <alias> Tag ...........................................  52
      7.2.8. <public-key> Tag ......................................  52
      7.2.9. <reply-to> Tag ........................................  52
      7.2.10. <reply-address> Tag ..................................  52
      7.2.11. <attachments> Tag ....................................  53
      7.2.12. <collection> Tag .....................................  53
      7.2.13. <collection-name> Tag ................................  53
      7.2.14. <collection-file> Tag ................................  53
      7.2.15. <collection-type> Tag ................................  53
      7.2.16. <collection-description> Tag .........................  53
      7.2.17. <file> Tag ...........................................  53
      7.2.18. <file-name> Tag ......................................  54
      7.2.19. <file-type> Tag ......................................  54
      7.2.20. <file-description> Tag ...............................  54
      7.2.21. <subject> Tag ........................................  54
      7.2.22. <presentation> Tag ...................................  54
      7.2.23. <stylesheet> Tag .....................................  54
      7.2.24. <stylesheet-uri> Tag ..................... ...........  54
      7.2.25. <stylesheet-namespace> Tag ...........................  54
      7.2.26. <source> Tag .........................................  55
      7.2.27. <source-uri> Tag .....................................  55
      7.2.28. <source-type> Tag ....................................  55
      7.2.29. <plain-text> Tag .....................................  55
      7.2.30. <markup> Tag .........................................  55
   7.3. <markup> Organization of Types and Groups ..................  55
      7.3.1. <markup> Element Organization .........................  55
      7.3.2. <markup> Attribute Organization .......................  56
   7.4. <markup> Attributes ........................................  57
      7.4.1. id Attribute ..........................................  57
      7.4.2. title Attribute .......................................  57
      7.4.3. class Attribute .......................................  58
      7.4.4. role Attribute ........................................  58
      7.4.5. uri Attribute .........................................  58
      7.4.6. direction Attribute ...................................  58
      7.4.7. orientation Attribute .................................  58
      7.4.8. wrap Attribute ........................................  58
      7.4.9. section-language Attribute ............................  59
      7.4.10. span-column Attribute ................................  59
      7.4.11. span-row Attribute ...................................  59
      7.4.12. refer Attribute ......................................  59
      7.4.13. scope Attribute ......................................  59
      7.4.14. long-form Attribute ..................................  60
   7.5. <markup> Elements ..........................................  60
      7.5.1. <define-list> Tag .....................................  60
      7.5.2. <define-item> Tag .....................................  60
      7.5.3. <define-term> Tag .....................................  60

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      7.5.4. <definition> Tag ......................................  60
      7.5.5. <navigation-list> Tag .................................  61
      7.5.6. <navigation-item> Tag .................................  61
      7.5.7. <navigation-object> Tag ...............................  61
      7.5.8. <navigation-text> Tag .................................  62
      7.5.9. <order-list> Tag ......................................  62
      7.5.10. <unorder-list> Tag ...................................  62
      7.5.11. <list-item> Tag ......................................  62
      7.5.12. <form> Tag ...........................................  62
      7.5.13. <form-body> Tag ......................................  63
      7.5.14. <table> Tag ..........................................  63
      7.5.15. <head-row> Tag .......................................  63
      7.5.16. <table-row> Tag ......................................  63
      7.5.17. <head-cell> Tag ......................................  63
      7.5.18. <table-cell> Tag .....................................  64
      7.5.19. <section> Tag ........................................  64
      7.5.20. <block-code> Tag .....................................  64
      7.5.21. <block-quote> Tag ....................................  65
      7.5.22. <citation> Tag .......................................  65
      7.5.23. <heading> Tag ........................................  65
      7.5.24. <object> Tag .........................................  65
      7.5.25. <object-text> Tag ....................................  66
      7.5.26. <object-uri> Tag .....................................  66
      7.5.27. <object-type> Tag ....................................  66
      7.5.28. <paragraph> Tag ......................................  66
      7.5.29. <separator> Tag ......................................  66
      7.5.30. <short> Tag ..........................................  67
      7.5.31. <button> Tag .........................................  67
      7.5.32. <cite> Tag ...........................................  67
      7.5.33. <emphasis> Tag .......................................  67
      7.5.34. <identifier> Tag .....................................  67
      7.5.35. <quote> Tag ..........................................  67
      7.5.36. <format> Tag .........................................  68
      7.5.37. <strong> Tag .........................................  68
      7.5.38. <title> Tag ..........................................  68
8. Protocol Compatibility ..........................................  68
   8.1. Simple Mail Transfer Protocol (SMTP) .......................  68
   8.2. Post Office Protocol - Version 3 (POP3) ....................  69
   8.3. Internet Message Access Protocol - Version 4rev1 (IMAP) ....  69
   8.4. Requirements for Web Mail ..................................  69
9. References ......................................................  70
10. Acknowledgements ...............................................  73
11. Author's Address ...............................................  74

1. Introduction
   MML as a standard is both a language and a standard list of
   processing constraints upon that language.

1.1. Scope
   This document seeks to fully describe the specification and syntax
   rules of the actual language, the constraints upon processing that

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   language, and the inclusion of other standards or technologies.

1.2. Requirements
   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in RFC 2119 [34].

   If an implementation, feature, or constraint does not satisfy a
   requirement level of MUST or REQUIRED for its respective statement,
   clause, phrase, or section that implementation, feature, or
   constraint MUST be considered failed.  Under such a circumstance,
   known as conditional compliance, a MML document must not be
   transmitted.  The ideal MML document will satisfy all MUST, REQUIRED,
   and SHOULD conditions, known as unconditional compliance.

1.3. Terminology
   This document will use several terms to describe various features or
   components.

   tag
      A tag is a code command enclosed in angle brackets such as,
      "<strong>".  Every tag exists as pairs of an opening tag and a
      closing tag.  All closing tags are identical to their opening
      counter-part except that are preceded by a forward slash
      character, such as "</strong>".

   element
      The word "element" is synonymous and used interchangeably with the
      term "tag".

   simple block
      A simple block is a tag that is capable of containing text and/or
      line-level tags.

   complex block
      A complex block is a tag that is capable of containing simple
      blocks or complex blocks.

   line-level tag
      Line-level tags are only capable of existing in simple blocks.
      Line-level tags cannot contain other tags.

   processor
      The term processor is to refer to any application that processes,
      interprets, or seeks to process a MML document.  The term
      processor may typically refer to email client applications, but is
      not limited to such.  The term "MML processor" is directly
      synonymous to the term "mail client" used by other related
      specifications.


	  
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   accessibility
      Accessibility is the degree of ease from which any human is
      equally capable of receiving data intended for human consumption
      from the desired document or request.  Accessibility may refer to
      persons with a sensory disability, a motor disability, or software
      impairment.

   understandability
      Understandability is the degree of ability by which a technology
      can be learned and used by a person who has never seen or used the
      technology previously.  Understandability also refers to the
      lack of effort necessary for an experienced user to consume and
      process the technology.

   semantics
      Semantics refers to the degree of description provided by meta-
      data and syntax rules either statically or through nesting and
      hierarchal implementation thereof.  The objective of semantics is
      to provide the most expansive description of data intended for
      human consumption without that description interfering with
      understandability during reading or writing.

   structure
      Structure refers to the effectual organization of data only as a
      result of well organized meta-data containers into a rigid
      hierarchy.

   session
      In the context of MML the term session only refers to an instance
      of communication, which is defined by the <session></session>
      tags.

2. Philosophy of Design
   The philosophy of design represents a shell container of decisions
   whose intent is certain beneficial objectives and to identify
   negative consequences.  The design philosophies for MML creation are
   listed in order of most significant to less relevant.

2.1. Structure
   Structure is the primary design consideration influencing MML.  It is
   important that structure be the most important factor in the design
   of the language as all other design considerations are merely a
   result of the logic and conventions imposed by a well structured
   form.

   The primary difference between MML and other markup languages is that
   proper structure is mandatorily imposed upon a document author.  This
   rigid inflexibility produces several profoundly significant benefits
   that exist inherently, which would otherwise merely be referred as
   best use.  The cost that comes from such rigidness is an inability

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   put content absolutely anywhere in a document in hopes to circumvent
   a processor's short-comings.

2.2. Syntax Simplicity and Understandability
   Syntax in MML is rather simple.  It MUST be well-formed XML that
   conforms to the MML schema.  Every tag in MML must exist as a pair of
   opening and closing tags.  Syntax in MML is simple and always
   uniform.

   Tag names are English words and not abbreviations or shortcuts.  This
   is critical to understandability.  An abbreviation is a symbolic
   representation of its expanded value.  Although it may be faster to
   write <p> instead of <paragraph> we are saving time and physical
   effort only at the expense of increase mental effort.  If we know a
   <p> tag represents a paragraph then it becomes of a symbol of the
   word paragraph, which is a step of mental deduction.

   As humans we are rather so consumed by symbolic use that it seems a
   trivial effort to back out single step of symbolic deduction.  The
   savings become significantly more noticeable given the quantity of
   which meta-data often occurs in large mark up documents.  The end
   result is that it is lesser mentally exhausting to read a document
   with descriptive and simple meta-data using complete words.

2.3. Semantics
   Semantics are necessary for binding data, which is useful only to
   humans, and processing syntax, which is only useful to language
   processors.  The objectives of semantic processing is for semantic
   processors to parse human supplied data and make decisions upon data
   that result in output relative to human decisions.
   
   MML was designed with consideration for applying semantics in the
   least specific manner.  Tag names were created for understandability
   and not semantics.  Any benefit received to semantics is purely
   consequential.  There are two remedies to this intended lack of
   elaboration.  Every tag in the <markup> section of MML is granted use
   of the role attribute.  For the role attribute please see section
   7.4.4. role Attribute.  Hierarchal semantics are the primary
   unintended beneficiary of a rigid structure imposed upon the data.
   A combined use of the role attribute or the tag names and the
   hierarchal structure in which they exist is the second remedy for the
   lack of semantic elaboration.

   Even though conventions in MML were not created to directly benefit
   semantics the conventions of semantic languages, such as Resource
   Document Framework, were the primary influencing factor in creating
   the concepts and rules for imposing structure and tag hierarchy.





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2.4. Accessibility
   It is an important factor that all persons are equally capable of
   accessing, using, and understanding documents defined as MML.
   Accessibility is a lesser important design factor as many concerns of
   accessibility are addressed by proper use of semantics and
   understandability.  Usability is primarily a result of presentation
   of the data, which exceeds the scope of this document.
   
   There are constraints upon processing specified by this document that
   may serve to benefit accessibility.  See section 4.1. Processor
   Requirements and Constraints.

2.5. Presentation
   Presentation is perhaps the least concern of all design factors
   influencing MML.  All presentation will exist in either an external
   stylesheet(s) or the default presentational conventions supplied by
   the MML processor.

   This version of MML only recognizes Cascading Style Sheets and
   Extensible Stylesheet Language as presentation languages.  The
   degree of processing compliance afforded to those languages and
   which versions are process-able are processor specific concerns,
   which exceed the scope of this document.  Please see section
   3.4. Stylesheet Technologies for more information.
   
   MML processors should make no assumption that there is an implied
   default presentation that any tag, element, or concept must adhere
   to.  Please see section 

2.6. Security
   While security is always important it is of trivial concern to the
   describing of data, which is why security is an consideration for the
   design of MML, but is lowest priority.  Much of the effort in
   assuring MML data remains confidential and maintains integrity rests
   on the processing of the MML processor, the security of the protocols
   used to transport the data, and the general security practices of
   document authors.

   Nonrepudiation is the most important security consideration, except
   perhaps for encryption, concerning email.  The job of nonrepudiation
   rests most prominently with proper storage practices of documents by
   users and time/date stamps imposed by email processors on the arrival
   of mail documents.  MML does contribute to nonrepudiation by
   requiring a timestamp in a manner beyond user control.  Please see
   section 4.1.4. Session Time-stamp and 7.2.2. <session> Tag.

   MML does provide methods for specifying implementation of public key
   distribution to facilitate encryption.  Please see section 3.6.
   Public Key Infrastructure.



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   MML also implements a description scheme for every attached asset
   using MIME to identify various types of media.  Media can only be
   executed according to the specified MIME type value.  The intent is
   that a file that looks like a graphic a d has the file extension of a
   a graphic may actually be a malicious executable program, but if it
   has a specified MIME type of a graphic format it can only open as a
   graphic or it MUST fail to open.  For more information please see
   section 3.8. Multipurpose Internet Mail Extensions and section 4.1.3.
   MIME Execution Restriction.

3. External Technologies
   In order to advance the functionality of this technology it is
   necessary to incorporate use of prior existing standards.

3.1. Extensible Markup Language (XML) and W3C XML Schema
   MML is written in W3C XML Schema, which is written XML.  As a result
   MML code is case sensitive.  This means all tag names MUST be lower
   case.  XML also requires that all attribute values MUST be quoted,
   tags MUST be properly nested, and every opening tag MUST have a
   corresponding closing tag.  Failure to adhere to these syntax rules
   will result in the document not validating, which will cause it to
   not send.  Please see section 4.1.1. Validation for more information.

3.2. XForms
   XForms is the only form method specified in MML.  Where XForms usage
   is allowed it must be used in accordance with the XForms schema:
   http://www.w3.org/Markup/Forms/2002/XForms-Schema.xsd
   Processors MUST use XForms version 1.1 to be compliant with this
   version of MML.

3.3. Accessible Rich Internet Applications
   The standards specification Accessible Rich Internet Applications,
   WAI-ARIA, is not included into this version of MML due to the
   specification not being formalized at the time of this writing.
   WAI-ARIA is intended to be implemented in future versions of MML.
   For more information please see http://www.w3c.org/WAI/

3.4. Resource Document Framework
   Resource Document Framework, RDF, is not an included technology of
   this specification, however RDF did significantly influence design
   patterns of MML.  RDF implementation MAY occur as a server-side
   feature, an optional client specific feature, or a MML processor
   behavior feature.  RDF implementation MUST NOT interfere with
   conventions, syntax, data, or meta-data supplied in the document
   directly.  This is necessary so that a MML document maintains a
   pre-RDF existence for distribution to other users that may not be
   capable of processing RDF.  For more information please see
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3.5. Stylesheet Technologies
   This version of MML recognizes only Cascading Style Sheets (CSS) and
   Extensible Stylesheets Language (XSL) as stylesheet languages.  MML
   imposes no requirement to support stylesheets.  If a MML processor
   does attempt to support a particular stylesheet it SHOULD state what
   version is supported and SHOULD fully support that version according
   to its specification.  For more information on CSS please see
   http://www.w3.org/Style/CSS/  For more information on XSL please see
   http://www.w3.org/Style/XSL/

3.6. Behaviors and Scripting
   MML does not support any scripting or behavior technologies.  MML
   processors MUST NOT implement scripting in MML documents.  This
   version of MML does not provide a solution to likely cross-site
   scripting vulnerabilities, breaches of non-repudiation, or
   interference to the integrity of the data that may result from the
   execution of scripting.

3.7. Public Key Infrastructure
   MML supports the transfer of public keys by directly embedding the
   hash value of the public key into the document.  MML provides no
   support for specifications regarding encryption, data transport, or
   confidentiality.  These are application specific and protocol
   features that exceed the scope of this document.  Please see section
   7.2.8. <public-key> Tag for more information on MML implementation.
   For PKI specifications please see http://www.rsa.com/rsalabs/pkcs/

3.8  Uniform Resource Identifier
   Uniform Resource Identifier (URI) is a representation of an address
   to an external asset.  MML requires the use of URIs to specify
   locations any object or stylesheet.  Aside from text the only data
   that MAY be included directly into the document are public key
   hashes.  For additional information please refer to RFC 3305.

3.9. Multipurpose Internet Mail Extensions
   Multipurpose Internet Mail Extensions (MIME) is specification
   designed to support an expanded character set beyond the basic 7-bit
   ASCII natively supported by SMTP.  For more information on the MIME
   specification please refer to RFC 2045, RFC 2046, RFC 2047, RFC 4288,
   RFC 4289, and RFC 2077.

4. Processor Roles
   The role of a processor of MML is to conform to the following
   specified requirements.  Processors of MML are, however, allowed
   certain freedoms from presumption that are also specified.

   MML processors are encouraged to test the limits of innovation.
   Diversity, usability, and customization are necessary results of
   competition.  The intent of section 4.1. Processor Requirements and
   Constraints is to impose requirements upon MML processors to ensure
   the integrity of the language.  The intent of section 4.2. Processor

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   Allowances is to illustrate some areas where MML processor vendors
   are free to explore without fear of violating this specification.

4.1. Processor Requirements and Constraints
   The intent of imposing requirements and constraints unto the
   processor is to provide a uniform existence for data, meta-data, and
   syntax rules contained in a MML document not at the burden of a
   document author.
   
4.1.1. Validation
   It is absolutely essential that a MML MUST validate against the MML
   schema prior to transmission.  If a MML document does not validate it
   MUST NOT be transmitted as email across any email specific protocol
   or Hyper Text Transfer Protocol.  A MML processor is not REQUIRED to
   receive any malformed or invalid MML document.

   It is not invalid, according to the schema, for a session author to
   include empty tags, such as <style></style>.  Empty tags SHOULD be
   removed by the MML processor during validation.  Every tag SHOULD
   contain text, other tags, or both if so allowed.

4.1.2. RFC 2822/5322 Conformance
   A MML processor must create RFC 5322 conformant mail headers for
   backwards compatibility.  MML aware clients/servers are required to
   ignore this header data and instead rely only upon the header
   information specified within the document.  This is necessary to
   ensure seamless transactions with the SMTP protocol.  This header
   data must be created after the user submits a document for transport
   and prior to the document being transported.

4.1.3. Session Separation and Presentation
   MML processors MUST process each session of a MML document
   separately.  This means a stylesheet specified in one particular
   session MUST NOT be processed in another session on the same
   document.  For instance a background specified, via stylesheet, in
   one session cannot exist as a background in any other session unless
   so specified in each other session even if in the same document.

   A MML processor SHOULD allow session authors to alter the
   presentation of all elements and content in a session even if those
   elements or content exist outside the message body.  This is not a
   requirement because MML processors MAY choose to display the session
   header information only in their application shell.

4.1.4. Session Preservation
   All prior sessions received in a MML document MUST be preserved
   verbatim, including whitespace.  The only decision that MAY be made
   upon prior sessions is whether external assets can be processed.  A
   MML processor SHOULD take steps to prevent prior sessions from manual
   alteration by a session author.


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4.1.5. Character Set
   The official character set for this version of MML is UTF16.
   
4.1.6. Session Time-stamp
   A time-stamp attribute is REQUIRED for each <session> tag.  The value
   of this time-stamp must be based upon the session author's system
   clock.  This value must be written by the MML processor between the
   moment the session author submits the document for transmission and
   the actual transmission of the document.  If a value for the
   time-stamp attribute is supplied by the author the MML processor MUST
   write over with the correct value.  It is absolutely essential that
   this be executed effectively as a tool to establish nonrepudiation.

4.1.7. URI Resolution
   MML processors MUST set a standard timeout for any URI that is
   referenced in a MML document.  The length of that timeout MAY be
   determined by the MML processor.  A MML processor MAY or MAY not
   allow its user to adjust the timeout length.  If a MML processor
   cannot resolve any resource at its specified URI timeout that
   resource MUST fail.  If a URI is resolved but points to a location
   that is not the requested resource that resource MUST fail.

4.1.8. MIME Execution Restriction
   Every object, stylesheet, or other external resource MUST be
   processed strictly according to its specified MIME type.  If a
   resource does not match its associated MIME type it MUST NOT be
   executed.  A MML processor is not REQUIRED to process any external
   resource.

4.1.9. Caching
   External assets, such as stylesheets or objects, MUST be cacheable by
   the MML processor.  Caching significantly improves performs by
   reducing the demand for bandwidth and allowing access to content even
   when offline.  Options, configuration, and implementation MUST exist
   entirely at the discretion of the MML processor.

4.1.10. Local Processing
   MML processors MUST locally contain all required code components
   necessary to process and validate a MML document according to the
   MML schema.  These components can be obtained from the following
   list:

   * mml.xsd
   * http://www.w3.org/MarkUp/Forms/2002/XForms-Schema.xsd
   * http://www.w3.org/MarkUp/SCHEMA/xml-events-attribs-1.xsd
   * http://www.w3.org/2001/XMLSchema.xsd
   * http://www.w3.org/2001/03/xml.xsd
   * http://www.w3.org/2001/XMLSchema.dtd
   * http://www.w3.org/2001/datatypes.dtd
   * mime.xsd


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   MML processors MUST NOT require the use of a network or internet
   connection to process or validate a MML document.

4.1.11. MIME Catalogue
   A MML processor's list of MIME types for MUST exist as a local schema
   file.  This file MUST be available for editing by either an
   administrator or common user.  Adding new MIME types to the list will
   likely result in a failure to process outside an internal network.
   Removing MIME types from the list MUST result in a failure to process
   media of those types.  By default the values in the MIME catalogue
   file will be every IANA registered type.

4.1.12. From and Reply-to Tags
   The <from> and <reply-to> tags are required tags, so the tags will
   exist even if their content is null.  If their content is null the
   MML processor MUST supply default values of the session author's
   email address to the <mail-address> child of <from> and the
   <reply-address>.  This MML processor supplied default content MUST be
   supplied by the MML processor between the moment the session author
   submits the document for transmission and the sending of the actual
   document.

   Session authors are allowed to specify content for these elements to
   hide their email address.  The benefit is to customize how other
   session authors can control direct traffic, such as reply and forward
   traffic, back to their email address.  It is to understand the actual
   benefit of these fields as they offer absolutely no security
   advantage.  MML processors MUST NOT use, process, or regulate the
   <from> or <reply-to> tags for any intent related to security.  Email
   transmission protocols operate in unencrypted plain-text by default,
   which is where any user can easily find any address or identity
   information.

   Please see section 7.2.4. <to>, <copy>,  blind-Copy>, and <from> Tags
   and section 7.2.9. <reply-to>.

4.1.13. Attachments
   Attachments MUST be sent with the actual MML document.  Attachments
   are not REQUIRED to be persistent.  Persistence is a design choice of
   MML processor vendors.  Attachment persistence refers to whether or
   not attachments will continue to be sent with the MML document after
   the document arrives at its intended destination(s).  A MML processor
   SHOULD allow users to choose to allow persistence.

   Attachments MUST be processed only according to their specified type.
   A MML processor is not REQUIRED to process any attachment.  The type
   specified for <collection-type> must represent every file in that
   respective <collection>.  If the <collection-type> tag is not present
   the files located in the collection MUST NOT be executable from the
   MML processor, MML document, or mail environment.

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4.1.14. Processing of <plain-text>
   Content provided in <plain-text> MUST be processed as plain text
   characters and/or whitespace only.  Code MUST NOT be processed in
   this tag.

4.1.15. Processing of style Attribute
   The value supplied by the style attribute is defined in the MML
   schema as lowercase alpha characters, uppercase alpha characters,
   and/or numbers plus a color character (:) plus lowercase alpha
   characters, uppercase alpha characters, and/or numbers.  The
   characters supplied prior to the color MUST represent the value
   supplied in a <stylesheet-namespace> element of the same session.
   The value supplied after the color must represent a reusable
   processing declaration defined inside the stylesheet, such as a CSS
   class.  An example of a supplied value: "namespaceName:CSSclass09".

   MML processors are not REQUIRED to process stylesheets.  If the noted
   stylesheet cannot be resolved or if the value supplied by the style
   attribute is either malformed or fails to match a stylesheet of the
   same session this attribute MUST NOT be processed.

4.1.16. Internationalization Attribute Processing
   Text MUST be processed in accordance with the defined values for the
   four internationalization attributes.  For processing descriptions
   please refer to these sections:
      * section 7.4.6. direction Attribute
      * section 7.4.7. orientation Attribute
      * section 7.4.8. wrap Attribute
      * section 7.4.9. section-language Attribute

   Failure to comply with internationalization MUST result in standards
   failure of this specification.

4.1.17. refer Attribute Processing
   The refer attribute MUST NOT be allowed to reference id values
   outside its <markup> container.  For more information see 7.4.12
   refer Attribute.

4.2. Processor Allowances
   This document does not exist to define the role of MML processors for
   features that exceed the scope of this document.  This section only
   serves to dispel assumptions and specify certain freedoms allowed to
   MML processors that may not be allowed to processors of other markup
   languages.

4.2.1. Default Presentation
   This specification does not make any statements regarding
   presentation of the language.  This means a MML processor is free to
   determine the default presentation for tags and objects.  This
   default presentation MAY apply to any or all parts of a MML document.
   This means that presentation provided from a MML processor fits a
   wider scope than presentation specified by a MML author since any MML

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   author can only specify presentation by use of an external stylesheet
   and stylesheet processing is limited to its session of the document.

   MML processor default presentation MUST be lower priority than
   presentation defined in a stylesheet.  If a conflict in presentation
   arises between the default and a stylesheet the presentation
   specified by the stylesheet MUST dominate even in regards to
   cascading.
   
   This means a MML processor determines font size, color, font, and so
   on until so specified by a stylesheet.  A MML processor determines,
   by default, whether complex and simple blocks impose a line break,
   wrap, float, or so on.

   A MML processor MAY or MAY not allow a user to customize or alter its
   default presentation.  This specification will not mandate
   customization, however, accessibility concerns SHOULD be considered
   for changing text size, turning off stylesheets, and replacing
   objects with their respective text content.

4.2.2. Default Behaviors
   This specification states not directive for behaviors or controls
   upon the data or the usability thereof.  There is no convention for
   allowing scripting in MML and any scripting that does exist MUST be
   processed as plain text content.  MML processors SHOULD allow
   behaviors that increase accessibility more importantly than
   usability.

   Section 3.3. Resource Document Framework states that RDF is not an
   included technology in this specification and MUST NOT interfere
   with conventions, syntax, data, or meta-data supplied in the document
   directly.  What it does not say is that semantic technologies MAY be
   used to auto-fill many areas of MML based upon a user's data habits.
   Semantic technologies may also be used for searching, data sorting,
   or other features.

5. Default mime.xsd
<?xml version="1.0" encoding="utf-8" ?>
<xs:schema elementFormDefault="qualified"
xmlns:xs="http://www.w3.org/2001/XMLSchema">
  <xs:simpleType name="application-type">
    <xs:restriction base="xs:token">
      <xs:enumeration value="activemessage" />
      <xs:enumeration value="andrew-inset" />
      <xs:enumeration value="applefile" />
      <xs:enumeration value="atom+xml" />
      <xs:enumeration value="atomicmail" />
      <xs:enumeration value="atomcat+xml" />
      <xs:enumeration value="atomsvc+xml" />
      <xs:enumeration value="auth-policy+xml" />
      <xs:enumeration value="batch-SMTP" />

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      <xs:enumeration value="beep+xml" />
      <xs:enumeration value="cals-1840" />
      <xs:enumeration value="ccxml+xml" />
      <xs:enumeration value="cellml+xml" />
      <xs:enumeration value="cnrp+xml" />
      <xs:enumeration value="commonground" />
      <xs:enumeration value="conference-info+xml" />
      <xs:enumeration value="cpl+xml" />
      <xs:enumeration value="csta+xml" />
      <xs:enumeration value="CSTAdata+xml" />
      <xs:enumeration value="cybercash" />
      <xs:enumeration value="davmount+xml" />
      <xs:enumeration value="dca-rft" />
      <xs:enumeration value="dec-dx" />
      <xs:enumeration value="dialog-info+xml" />
      <xs:enumeration value="dicom" />
      <xs:enumeration value="dns" />
      <xs:enumeration value="dvcs" />
      <xs:enumeration value="ecmascript" />
      <xs:enumeration value="EDI-Consent" />
      <xs:enumeration value="EDIFACT" />
      <xs:enumeration value="EDI-X12" />
      <xs:enumeration value="epp+xml" />
      <xs:enumeration value="eshop" />
      <xs:enumeration value="example" />
      <xs:enumeration value="fastinfoset" />
      <xs:enumeration value="fastsoap" />
      <xs:enumeration value="fits" />
      <xs:enumeration value="font-tdpfr" />
      <xs:enumeration value="H224" />
      <xs:enumeration value="http" />
      <xs:enumeration value="hyperstudio" />
      <xs:enumeration value="iges" />
      <xs:enumeration value="im-iscomposing+xml" />
      <xs:enumeration value="index" />
      <xs:enumeration value="index.cmd" />
      <xs:enumeration value="index.obj" />
      <xs:enumeration value="index.response" />
      <xs:enumeration value="index.vnd" />
      <xs:enumeration value="iotp" />
      <xs:enumeration value="ipp" />
      <xs:enumeration value="isup" />
      <xs:enumeration value="javascript" />
      <xs:enumeration value="json" />
      <xs:enumeration value="kpml-request+xml" />
      <xs:enumeration value="kpml-response+xml" />
      <xs:enumeration value="lost+xml" />
      <xs:enumeration value="mac-binhex40" />
      <xs:enumeration value="macwriteii" />
      <xs:enumeration value="marc" />
      <xs:enumeration value="mathematica" />

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      <xs:enumeration
      value="mbms-associated-procedure-description+xml" />
      <xs:enumeration value="mbms-deregister+xml" />
      <xs:enumeration value="mbms-envelope+xml" />
      <xs:enumeration value="mbms-msk-response+xml" />
      <xs:enumeration value="mbms-msk+xml" />
      <xs:enumeration value="mbms-protection-description+xml" />
      <xs:enumeration value="mbms-reception-report+xml" />
      <xs:enumeration value="mbms-register-response+xml" />
      <xs:enumeration value="mbms-register+xml" />
      <xs:enumeration value="mbms-user-service-description+xml" />
      <xs:enumeration value="mbox" />
      <xs:enumeration value="media_control+xml" />
      <xs:enumeration value="mediaservercontrol+xml" />
      <xs:enumeration value="mikey" />
      <xs:enumeration value="moss-keys" />
      <xs:enumeration value="moss-signature" />
      <xs:enumeration value="mosskey-data" />
      <xs:enumeration value="mosskey-request" />
      <xs:enumeration value="mpeg4-generic" />
      <xs:enumeration value="mpeg4-iod" />
      <xs:enumeration value="mpeg4-iod-xmt" />
      <xs:enumeration value="mp4" />
      <xs:enumeration value="msword" />
      <xs:enumeration value="mxf" />
      <xs:enumeration value="nasdata" />
      <xs:enumeration value="news-transmission" />
      <xs:enumeration value="nss" />
      <xs:enumeration value="ocsp-request" />
      <xs:enumeration value="ocsp-response" />
      <xs:enumeration value="octet-stream" />
      <xs:enumeration value="oda" />
      <xs:enumeration value="oebps-package+xml" />
      <xs:enumeration value="ogg" />
      <xs:enumeration value="parityfec" />
      <xs:enumeration value="patch-ops-error+xml" />
      <xs:enumeration value="pdf" />
      <xs:enumeration value="pgp-encrypted" />
      <xs:enumeration value="pgp-keys" />
      <xs:enumeration value="pgp-signature" />
      <xs:enumeration value="pidf+xml" />
      <xs:enumeration value="pidf-diff+xml" />
      <xs:enumeration value="pkcs10" />
      <xs:enumeration value="pkcs7-mime" />
      <xs:enumeration value="pkcs7-signature" />
      <xs:enumeration value="pkix-cert" />
      <xs:enumeration value="pkixcmp" />
      <xs:enumeration value="pkix-crl" />
      <xs:enumeration value="pkix-pkipath" />
      <xs:enumeration value="pls+xml" />
      <xs:enumeration value="poc-settings+xml" />

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      <xs:enumeration value="postscript" />
      <xs:enumeration value="prs.alvestrand.titrax-sheet" />
      <xs:enumeration value="prs.cww" />
      <xs:enumeration value="prs.nprend" />
      <xs:enumeration value="prs.plucker" />
      <xs:enumeration value="qsig" />
      <xs:enumeration value="rdf+xml" />
      <xs:enumeration value="reginfo+xml" />
      <xs:enumeration value="relax-ng-compact-syntax" />
      <xs:enumeration value="remote-printing" />
      <xs:enumeration value="resource-lists+xml" />
      <xs:enumeration value="riscos" />
      <xs:enumeration value="rlmi+xml" />
      <xs:enumeration value="rls-services+xml" />
      <xs:enumeration value="rtf" />
      <xs:enumeration value="rtx" />
      <xs:enumeration value="samlassertion+xml" />
      <xs:enumeration value="samlmetadata+xml" />
      <xs:enumeration value="sbml+xml" />
      <xs:enumeration value="scvp-cv-request" />
      <xs:enumeration value="scvp-cv-response" />
      <xs:enumeration value="scvp-vp-request" />
      <xs:enumeration value="scvp-vp-response" />
      <xs:enumeration value="sdp" />
      <xs:enumeration value="set-payment" />
      <xs:enumeration value="set-payment-initiation" />
      <xs:enumeration value="set-registration" />
      <xs:enumeration value="set-registration-initiation" />
      <xs:enumeration value="sgml" />
      <xs:enumeration value="sgml-open-catalog" />
      <xs:enumeration value="shf+xml" />
      <xs:enumeration value="sieve" />
      <xs:enumeration value="simple-filter+xml" />
      <xs:enumeration value="simple-message-summary" />
      <xs:enumeration value="simpleSymbolContainer" />
      <xs:enumeration value="slate" />
      <xs:enumeration value="smil+xml" />
      <xs:enumeration value="soap+fastinfoset" />
      <xs:enumeration value="soap+xml" />
      <xs:enumeration value="sparql-query" />
      <xs:enumeration value="sparql-results+xml" />
      <xs:enumeration value="spirits-event+xml" />
      <xs:enumeration value="srgs" />
      <xs:enumeration value="srgs+xml" />
      <xs:enumeration value="ssml+xml" />
      <xs:enumeration value="timestamp-query" />
      <xs:enumeration value="timestamp-reply" />
      <xs:enumeration value="tve-trigger" />
      <xs:enumeration value="ulpfec" />
      <xs:enumeration value="vemmi" />
      <xs:enumeration value="vnd.3gpp.bsf+xml" />

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      <xs:enumeration value="vnd.3gp.pic-bw-large" />
      <xs:enumeration value="vnd.3gp.pic-bw-small" />
      <xs:enumeration value="vnd.3gp.pic-bw-var" />
      <xs:enumeration value="vnd.3gp.sms" />
      <xs:enumeration value="vnd.3gp2.bcmcsinfo+xml" />
      <xs:enumeration value="vnd.3gp2.sms" />
      <xs:enumeration value="vnd.3gp2.tcap" />
      <xs:enumeration value="vnd.3M.Post-in-Notes" />
      <xs:enumeration value="vnd.accpac.simply.aso" />
      <xs:enumeration value="vnd.accpac.simply.imp" />
      <xs:enumeration value="vnd.acucobol" />
      <xs:enumeration value="vnd.acucorp" />
      <xs:enumeration value="vnd.adobe.xdp+xml" />
      <xs:enumeration value="vnd.adobe.xfdf" />
      <xs:enumeration value="vnd.aether.imp" />
      <xs:enumeration value="vnd.americandynamics.acc" />
      <xs:enumeration value="vnd.amiga.ami" />
      <xs:enumeration
      value="vnd.anser-web-certificate-issue-initiation" />
      <xs:enumeration value="vnd.antix.game-component" />
      <xs:enumeration value="vnd.apple.installer+xml" />
      <xs:enumeration value="vnd.arastra.swi" />
      <xs:enumeration value="vnd.audiograph" />
      <xs:enumeration value="vnd.autopackage" />
      <xs:enumeration value="vnd.avistar+xml" />
      <xs:enumeration value="vnd.blueice.multipass" />
      <xs:enumeration value="vnd.bmi" />
      <xs:enumeration value="vnd.businessobjects" />
      <xs:enumeration value="vnd.cab-jscript" />
      <xs:enumeration value="vnd.canon-cpdl" />
      <xs:enumeration value="vnd.canon-lips" />
      <xs:enumeration value="vnd.cendio.thinlinc.clientconf" / 
      <xs:enumeration value="vnd.chemdraw+xml" />
      <xs:enumeration value="vnd.chipnuts.karaoke-mmd" />
      <xs:enumeration value="vnd.cinderella" />
      <xs:enumeration value="vnd.cirpack.isdn-ext" />
      <xs:enumeration value="vnd.claymore" />
      <xs:enumeration value="vnd.clonk.c4group" />
      <xs:enumeration value="vnd.commerce-battelle" />
      <xs:enumeration value="vnd.comonspace" />
      <xs:enumeration value="vnd.cosmocaller" />
      <xs:enumeration value="vnd.contact.cmsg" />
      <xs:enumeration value="vnd.crick.clicker" />
      <xs:enumeration value="vnd.crick.clicker.keyboard" />
      <xs:enumeration value="vnd.crick.clicker.palette" />
      <xs:enumeration value="vnd.crick.clicker.template" />
      <xs:enumeration value="vnd.crick.clicker.wordbank" />
      <xs:enumeration value="vnd.criticaltools.wbs+xml" />
      <xs:enumeration value="vnd.ctc-posml" />
      <xs:enumeration value="vnd.ctct.ws+xml" />
      <xs:enumeration value="vnd.cups-pdf" />

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      <xs:enumeration value="vnd.cups-postscript" />
      <xs:enumeration value="vnd.cups-ppd" />
      <xs:enumeration value="vnd.cups-raster" />
      <xs:enumeration value="vnd.cups-raw" />
      <xs:enumeration value="vnd.curl" />
      <xs:enumeration value="vnd.cybank" />
      <xs:enumeration value="vnd.data-vision.rdf" />
      <xs:enumeration value="vnd.denovo.fcselayout-link" />
      <xs:enumeration value="vnd.dna" />
      <xs:enumeration value="vnd.dpgraph" />
      <xs:enumeration value="vnd.dreamfactory" />
      <xs:enumeration value="vnd.dvb.esgcontainer" />
      <xs:enumeration value="vnd.dvb.ipdcesgaccess" />
      <xs:enumeration value="vnd.dvb.iptv.alfec-base" />
      <xs:enumeration value="vnd.dvb.iptv.alfec-enhancement" />
      <xs:enumeration value="vnd.dxr" />
      <xs:enumeration value="vnd.ecdis-update" />
      <xs:enumeration value="vnd.ecowin.chart" />
      <xs:enumeration value="vnd.ecowin.filerequest" />
      <xs:enumeration value="vnd.ecowin.fileupdate" />
      <xs:enumeration value="vnd.ecowin.series" />
      <xs:enumeration value="vnd.ecowin.seriesrequest" />
      <xs:enumeration value="vnd.ecowin.seriesupdate" />
      <xs:enumeration value="vnd.enliven" />
      <xs:enumeration value="vnd.epson.esf" />
      <xs:enumeration value="vnd.epson.msf" />
      <xs:enumeration value="vnd.epson.quickanime" />
      <xs:enumeration value="vnd.epson.salt" />
      <xs:enumeration value="vnd.epson.ssf" />
      <xs:enumeration value="vnd.ericsson.quickcall" />
      <xs:enumeration value="vnd.eszigno3+xml" />
      <xs:enumeration value="vnd.eudora.data" />
      <xs:enumeration value="vnd.ezpix-album" />
      <xs:enumeration value="vnd.fdf" />
      <xs:enumeration value="vnd.ffsns" />
      <xs:enumeration value="vnd.fints" />
      <xs:enumeration value="vnd.FloGraphIt" />
      <xs:enumeration value="vnd.fluxtime.clip" />
      <xs:enumeration value="vnd.font-fontforge-sfd" />
      <xs:enumeration value="vnd.framemaker" />
      <xs:enumeration value="vnd.frogans.fnc" />
      <xs:enumeration value="vnd.frogans.ltf" />
      <xs:enumeration value="vnd.fsc.weblaunch" />
      <xs:enumeration value="vnd.fujitsu.oasys" />
      <xs:enumeration value="vnd.fujitsu.oasys2" />
      <xs:enumeration value="vnd.fujitsu.oasys3" />
      <xs:enumeration value="vnd.fujitsu.oasysgp" />
      <xs:enumeration value="vnd.fujitsu.oasysprs" />
      <xs:enumeration value="vnd.fujixerox.ART4" />
      <xs:enumeration value="vnd.fujixerox.ART-EX" />
      <xs:enumeration value="vnd.fujixerox.ddd" />

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      <xs:enumeration value="vnd.fujixerox.docuworks" />
      <xs:enumeration value="vnd.fujixerox.docuworks.binder" />
      <xs:enumeration value="vnd.fujixerox.HBPL" />
      <xs:enumeration value="vnd.fut-misnet" />
      <xs:enumeration value="vnd.fuzzysheet" />
      <xs:enumeration value="vnd.genomatix.tuxedo" />
      <xs:enumeration value="vnd.google-earth.kml+xml" />
      <xs:enumeration value="vnd.google-earth.kmz" />
      <xs:enumeration value="vnd.grafeq" />
      <xs:enumeration value="vnd.gridmp" />
      <xs:enumeration value="vnd.groove-account" />
      <xs:enumeration value="vnd.groove-help" />
      <xs:enumeration value="vnd.groove-identity-message" />
      <xs:enumeration value="vnd.groove-injector" />
      <xs:enumeration value="vnd.groove-tool-message" />
      <xs:enumeration value="vnd.groove-tool-template" />
      <xs:enumeration value="vnd.groove-vcard" />
      <xs:enumeration value="vnd.HandHeld-Entertainment+xml" />
      <xs:enumeration value="vnd.hbci" />
      <xs:enumeration value="vnd.hcl-bireports" />
      <xs:enumeration value="vnd.hhe.lesson-player" />
      <xs:enumeration value="vnd.hp-HPGL" />
      <xs:enumeration value="vnd.hp-hpid" />
      <xs:enumeration value="vnd.hp-hps" />
      <xs:enumeration value="vnd.hp-jlyt" />
      <xs:enumeration value="vnd.hp-PCL" />
      <xs:enumeration value="vnd.hp-PCLXL" />
      <xs:enumeration value="vnd.httphone" />
      <xs:enumeration value="vnd.hydrostatix.sof-data" />
      <xs:enumeration value="vnd.hzn-3d-crossword" />
      <xs:enumeration value="vnd.ibm.afplinedata" />
      <xs:enumeration value="vnd.ibm.electronic-media" />
      <xs:enumeration value="vnd.ibm.MiniPay" />
      <xs:enumeration value="vnd.ibm.modcap" />
      <xs:enumeration value="vnd.ibm.rights-management" />
      <xs:enumeration value="vnd.ibm.secure-container" />
      <xs:enumeration value="vnd.iccprofile" />
      <xs:enumeration value="vnd.igloader" />
      <xs:enumeration value="vnd.immervision-ivp" />
      <xs:enumeration value="vnd.immervision-ivu" />
      <xs:enumeration value="vnd.informedcontrol.rms+xml" />
      <xs:enumeration value="vnd.informix-visionary" />
      <xs:enumeration value="vnd.intercon.formnet" />
      <xs:enumeration value="vnd.intertrust.digibox" />
      <xs:enumeration value="vnd.intertrust.nncp" />
      <xs:enumeration value="vnd.intu.qbo" />
      <xs:enumeration value="vnd.intu.qfx" />
      <xs:enumeration value="vnd.iptc.g2.conceptitem+xml" />
      <xs:enumeration value="vnd.iptc.g2.knowledgeitem+xml" />
      <xs:enumeration value="vnd.iptc.g2.newsitem+xml" />
      <xs:enumeration value="vnd.iptc.g2.packageitem+xml" />

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      <xs:enumeration value="vnd.ipunplugged.rcprofile" />
      <xs:enumeration value="vnd.irepository.package+xml" />
      <xs:enumeration value="vnd.is-xpr" />
      <xs:enumeration value="vnd.jam" />
      <xs:enumeration value="vnd.japannet-directory-service" />
      <xs:enumeration value="vnd.japannet-ipnstore-wakeup" />
      <xs:enumeration value="vnd.japannet-payment-wakeup" />
      <xs:enumeration value="vnd.japannet-registration" />
      <xs:enumeration value="vnd.japannet-registration-wakeup" />
      <xs:enumeration value="vnd.japannet-setstore-wakeup" />
      <xs:enumeration value="vnd.japannet-verification" />
      <xs:enumeration value="vnd.japannet-japannet--wakeup" />
      <xs:enumeration value="vnd.jcp.javame.midlet-rms" />
      <xs:enumeration value="vnd.jisp" />
      <xs:enumeration value="vnd.joost.joda-archive" />
      <xs:enumeration value="vnd.kahootz" />
      <xs:enumeration value="vnd.kde.karbon" />
      <xs:enumeration value="vnd.kde.kchart" />
      <xs:enumeration value="vnd.kde.kformula" />
      <xs:enumeration value="vnd.kde.kivio" />
      <xs:enumeration value="vnd.kde.kontour" />
      <xs:enumeration value="vnd.kde.kpresenter" />
      <xs:enumeration value="vnd.kde.kspread" />
      <xs:enumeration value="vnd.kde.kword" />
      <xs:enumeration value="vnd.ken meaapp" />
      <xs:enumeration value="vnd.kidspiration" />
      <xs:enumeration value="vnd.Kinar" />
      <xs:enumeration value="vnd.koan" />
      <xs:enumeration value="vnd.kodak-descriptor" />
      <xs:enumeration value="vnd.liberty-request+xml" />
      <xs:enumeration value="vnd.llamagraphics.life-balance.desktop" />
      <xs:enumeration
      value="vnd.llamagraphics.life-balance.exchange+xml" />
      <xs:enumeration value="vnd.lotus-1-2-3" />
      <xs:enumeration value="vnd.lotus-approach" />
      <xs:enumeration value="vnd.lotus-freelance" />
      <xs:enumeration value="vnd.lotus-notes" />
      <xs:enumeration value="vnd.lotus-organizer" />
      <xs:enumeration value="vnd.lotus-screencam" />
      <xs:enumeration value="vnd.lotus-wordpro" />
      <xs:enumeration value="vnd.macports.portpkg" />
      <xs:enumeration value="vnd.marlin.drm.actiontoken+xml" />
      <xs:enumeration value="vnd.marlin.drm.conftoken+xml" />
      <xs:enumeration value="vnd.marlin.drm.license+xml" />
      <xs:enumeration value="vnd.marlin.drm.mdcf" />
      <xs:enumeration value="vnd.mcd" />
      <xs:enumeration value="vnd.medcalcdata" />
      <xs:enumeration value="vnd.mediastation.cdkey" />
      <xs:enumeration value="vnd.meridian-slingshot" />
      <xs:enumeration value="vnd.MFER" />
      <xs:enumeration value="vnd.mfmp" />

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      <xs:enumeration value="vnd.micrografx.flo" />
      <xs:enumeration value="vnd.micrografx.igx" />
      <xs:enumeration value="vnd.mif" />
      <xs:enumeration value="vnd.minisoft-hp3000-save" />
      <xs:enumeration value="vnd.mitsubishi.misty-guard.trustweb" />
      <xs:enumeration value="vnd.Mobius.DAF" />
      <xs:enumeration value="vnd.Mobius.DIS" />
      <xs:enumeration value="vnd.Mobius.MBK" />
      <xs:enumeration value="vnd.Mobius.MQY" />
      <xs:enumeration value="vnd.Mobius.MSL" />
      <xs:enumeration value="vnd.Mobius.PLC" />
      <xs:enumeration value="vnd.Mobius.TXF" />
      <xs:enumeration value="vnd.mophun.application" />
      <xs:enumeration value="vnd.mophun.certificate" />
      <xs:enumeration value="vnd.motorola.flexsuite" />
      <xs:enumeration value="vnd.motorola.flexsuite.adsi" />
      <xs:enumeration value="vnd.motorola.flexsuite.fis" />
      <xs:enumeration value="vnd.motorola.flexsuite.gotap" />
      <xs:enumeration value="vnd.motorola.flexsuite.kmr" />
      <xs:enumeration value="vnd.motorola.flexsuite.ttc" />
      <xs:enumeration value="vnd.motorola.flexsuite.wem" />
      <xs:enumeration value="vnd.mozilla.xul+xml" />
      <xs:enumeration value="vnd.ms-artgalry" />
      <xs:enumeration value="vnd.ms-asf" />
      <xs:enumeration value="vnd.ms-cab-compressed" />
      <xs:enumeration value="vnd.ms-excel" />
      <xs:enumeration value="vnd.ms-fontobject" />
      <xs:enumeration value="vnd.ms-htmlhelp" />
      <xs:enumeration value="vnd.ms-ims" />
      <xs:enumeration value="vnd.ms-lrm" />
      <xs:enumeration value="vnd.ms-playready.initiator+xml" />
      <xs:enumeration value="vnd.ms-powerpoint" />
      <xs:enumeration value="vnd.ms-project" />
      <xs:enumeration value="vnd.ms-tnef" />
      <xs:enumeration value="vnd.ms-wmdrm.lic-chlg-req" />
      <xs:enumeration value="vnd.ms-wmdrm.lic-resp" />
      <xs:enumeration value="vnd.ms-wmdrm.meter-chlg-req" />
      <xs:enumeration value="vnd.ms-wmdrm.meter-resp" />
      <xs:enumeration value="vnd.ms-works" />
      <xs:enumeration value="vnd.ms-wpl" />
      <xs:enumeration value="vnd.ms-xpsdocument" />
      <xs:enumeration value="vnd.mseq" />
      <xs:enumeration value="vnd.msign" />
      <xs:enumeration value="vnd.multiad.creator" />
      <xs:enumeration value="vnd.multiad.creator.cif" />
      <xs:enumeration value="vnd.musician" />
      <xs:enumeration value="vnd.music-niff" />
      <xs:enumeration value="vnd.muvee.style" />
      <xs:enumeration value="vnd.ncd.control" />
      <xs:enumeration value="vnd.ncd.reference" />
      <xs:enumeration value="vnd.nervana" />

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      <xs:enumeration value="vnd.netfpx" />
      <xs:enumeration value="vnd.neurolanguage.nlu" />
      <xs:enumeration value="vnd.noblenet-directory" />
      <xs:enumeration value="vnd.noblenet-sealer" />
      <xs:enumeration value="vnd.noblenet-web" />
      <xs:enumeration value="vnd.nokia.catalogs" />
      <xs:enumeration value="vnd.nokia.conml+wbxml" />
      <xs:enumeration value="vnd.nokia.conml+xml" />
      <xs:enumeration value="vnd.nokia.iptv.config+xml" />
      <xs:enumeration value="vnd.nokia.iSDS-radio-presets" />
      <xs:enumeration value="vnd.nokia.landmark+xml" />
      <xs:enumeration value="vnd.nokia.landmarkcollection+xml" />
      <xs:enumeration value="vnd.nokia.ncd" />
      <xs:enumeration value="vnd.nokia.n-gage.ac+xml" />
      <xs:enumeration value="vnd.nokia.n-gage.data" />
      <xs:enumeration value="vnd.nokia.n-gage.symbian.install" />
      <xs:enumeration value="vnd.nokia.pcd+wbxml" />
      <xs:enumeration value="vnd.nokia.pcd+xml" />
      <xs:enumeration value="vnd.nokia.radio-preset" />
      <xs:enumeration value="vnd.nokia.radio-presets" />
      <xs:enumeration value="vnd.novadigm.EDM" />
      <xs:enumeration value="vnd.novadigm.EDX" />
      <xs:enumeration value="vnd.novadigm.EXT" />
      <xs:enumeration value="vnd.oasis.opendocument.chart" />
      <xs:enumeration value="vnd.oasis.opendocument.chart-template" />
      <xs:enumeration value="vnd.oasis.opendocument.formula" />
      <xs:enumeration value="vnd.oasis.opendocument.formula-template" />
      <xs:enumeration value="vnd.oasis.opendocument.graphics" />
      <xs:enumeration
      value="vnd.oasis.opendocument.graphics-template" />
      <xs:enumeration value="vnd.oasis.opendocument.image" />
      <xs:enumeration value="vnd.oasis.opendocument.image-template" />
      <xs:enumeration value="vnd.oasis.opendocument.presentation" />
      <xs:enumeration
      value="vnd.oasis.opendocument.presentation-template" />
      <xs:enumeration value="vnd.oasis.opendocument.spreadsheet" />
      <xs:enumeration
      value="vnd.oasis.opendocument.spreadsheet-template" />
      <xs:enumeration value="vnd.oasis.opendocument.text" />
      <xs:enumeration value="vnd.oasis.opendocument.text-master" />
      <xs:enumeration value="vnd.oasis.opendocument.text-template" />
      <xs:enumeration value="vnd.oasis.opendocument.text-web" />
      <xs:enumeration value="vnd.obn" />
      <xs:enumeration value="vnd.olpc-sugar" />
      <xs:enumeration
      value="vnd.oma.bcast.asssociated-procedure-parameter+xml" />
      <xs:enumeration value="vnd.oma.bcast.drm-trigger+xml" />
      <xs:enumeration value="vnd.oma.bcast.imd+xml" />
      <xs:enumeration value="vnd.oma.bcast.ltkm" />
      <xs:enumeration value="vnd.oma.bcast.notification+xml" />
      <xs:enumeration value="vnd.oma.bcast.sgboot" />

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      <xs:enumeration value="vnd.oma.bcast.sgdd+xml" />
      <xs:enumeration value="vnd.oma.bcast.sgdu" />
      <xs:enumeration value="vnd.oma.bcast.simple-symbol-container" />
      <xs:enumeration value="vnd.oma.bcast.smartcard-trigger+xml" />
      <xs:enumeration value="vnd.oma.bcast.sprov+xml" />
      <xs:enumeration value="vnd.oma.bcast.stkm" />
      <xs:enumeration value="vnd.oma.dcd" />
      <xs:enumeration value="vnd.oma.dcdc" />
      <xs:enumeration value="vnd.oma.dd2+xml" />
      <xs:enumeration value="vnd.oma.drm.risd+xml" />
      <xs:enumeration value="vnd.oma.group-usage-list+xml" />
      <xs:enumeration
      value="vnd.oma.poc.detailed-progress-report+xml" />
      <xs:enumeration value="vnd.oma.poc.final-report+xml" />
      <xs:enumeration value="vnd.oma.groups+xml" />
      <xs:enumeration value="vnd.oma.invocation-descriptor+xml" />
      <xs:enumeration value="vnd.oma.optimized-progress-report+xml" />
      <xs:enumeration value="vnd.oma.xcap-directory+xml" />
      <xs:enumeration value="vnd.omads-email+xml" />
      <xs:enumeration value="vnd.omads-file+xml" />
      <xs:enumeration value="vnd.omads-folder+xml" />
      <xs:enumeration value="vnd.omaloc-sup-init" />
      <xs:enumeration value="vnd.oma-scws-http-request" />
      <xs:enumeration value="vnd.oma-scws-http-response" />
      <xs:enumeration value="vnd.openofficeorg.extension" />
      <xs:enumeration value="vnd.osa.netdeploy" />
      <xs:enumeration value="vnd.osgi.bundle" />
      <xs:enumeration value="vnd.osgi.dp" />
      <xs:enumeration value="vnd.otps.ct-kip+xml" />
      <xs:enumeration value="vnd.palm" />
      <xs:enumeration value="vnd.paos.xml" />
      <xs:enumeration value="vnd.pg.format" />
      <xs:enumeration value="vnd.pg.osasli" />
      <xs:enumeration value="vnd.piacess.application-license" />
      <xs:enumeration value="vnd.picsel" />
      <xs:enumeration value="vnd.poc.group-advertisement+xml" />
      <xs:enumeration value="vnd.pocketlearn" />
      <xs:enumeration value="vnd.powerbuilder6" />
      <xs:enumeration value="vnd.powerbuilder6-s" />
      <xs:enumeration value="vnd.powerbuilder7" />
      <xs:enumeration value="vnd.powerbuilder75" />
      <xs:enumeration value="vnd.powerbuilder75-s" />
      <xs:enumeration value="vnd.powerbuilder7-s" />
      <xs:enumeration value="vnd.preminet" />
      <xs:enumeration value="vnd.previewsystems.box" />
      <xs:enumeration value="vnd.proteus.magazine" />
      <xs:enumeration value="vnd.publishare-delta-tree" />
      <xs:enumeration value="vnd.pvi.ptid1" />
      <xs:enumeration value="vnd.pwg-multiplexed" />
      <xs:enumeration value="vnd.pwg-xhtml-print+xml" />
      <xs:enumeration value="vnd.qualcomm.brew-app-res" />

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      <xs:enumeration value="vnd.Quark.QuarkXPress" />
      <xs:enumeration value="vnd.rapid" />
      <xs:enumeration value="vnd.recordare.musicxml" />
      <xs:enumeration value="vnd.recordare.musicxml+xml" />
      <xs:enumeration value="vnd.RenLearn.rlprint" />
      <xs:enumeration value="vnd.route66.link66+xml" />
      <xs:enumeration value="vnd.ruckus.download" />
      <xs:enumeration value="vnd.s3sms" />
      <xs:enumeration value="vnd.sbm.cid" />
      <xs:enumeration value="vnd.sbm.mid2" />
      <xs:enumeration value="vnd.scribus" />
      <xs:enumeration value="vnd.sealed.3df" />
      <xs:enumeration value="vnd.sealed.csf" />
      <xs:enumeration value="vnd.sealed.doc" />
      <xs:enumeration value="vnd.sealed.eml" />
      <xs:enumeration value="vnd.sealed.mht" />
      <xs:enumeration value="vnd.sealed.net" />
      <xs:enumeration value="vnd.sealed.ppt" />
      <xs:enumeration value="vnd.sealed.tiff" />
      <xs:enumeration value="vnd.sealed.xls" />
      <xs:enumeration value="vnd.sealedmedia.softseal.html" />
      <xs:enumeration value="vnd.sealedmedia.softseal.pdf" />
      <xs:enumeration value="vnd.seemail" />
      <xs:enumeration value="vnd.sema" />
      <xs:enumeration value="vnd.semd" />
      <xs:enumeration value="vnd.semf" />
      <xs:enumeration value="vnd.shana.informed.formdata" />
      <xs:enumeration value="vnd.shana.informed.formtemplate" />
      <xs:enumeration value="vnd.shana.informed.interchange" />
      <xs:enumeration value="vnd.shana.informed.package" />
      <xs:enumeration value="vnd.SimTech-MindMapper" />
      <xs:enumeration value="vnd.smaf" />
      <xs:enumeration value="vnd.solent.sdkm+xml" />
      <xs:enumeration value="vnd.spotfire.dxp" />
      <xs:enumeration value="vnd.spotfire.sfs" />
      <xs:enumeration value="vnd.sss-cod" />
      <xs:enumeration value="vnd.sss-dtf" />
      <xs:enumeration value="vnd.sss-ntf" />
      <xs:enumeration value="vnd.street-stream" />
      <xs:enumeration value="vnd.sun.wadl+xml" />
      <xs:enumeration value="vnd.sus-calendar" />
      <xs:enumeration value="vnd.svd" />
      <xs:enumeration value="vnd.swiftview-ics" />
      <xs:enumeration value="vnd.syncml.dm+wbxml" />
      <xs:enumeration value="vnd.syncml.dm+xml" />
      <xs:enumeration value="vnd.syncml.ds.notification" />
      <xs:enumeration value="vnd.syncml+xml" />
      <xs:enumeration value="vnd.tao.intent-module-archive" />
      <xs:enumeration value="vnd.tmobile-livetv" />
      <xs:enumeration value="vnd.trid.tpt" />
      <xs:enumeration value="vnd.triscape.mxs" />

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      <xs:enumeration value="vnd.trueapp" />
      <xs:enumeration value="vnd.truedoc" />
      <xs:enumeration value="vnd.ufdl" />
      <xs:enumeration value="vnd.uig.theme" />
      <xs:enumeration value="vnd.umajin" />
      <xs:enumeration value="vnd.unity" />
      <xs:enumeration value="vnd.uoml+xml" />
      <xs:enumeration value="vnd.uplanet.alert" />
      <xs:enumeration value="vnd.uplanet.alert-wbxml" />
      <xs:enumeration value="vnd.uplanet.bearer-choice" />
      <xs:enumeration value="vnd.uplanet.bearer-choice-wbxml" />
      <xs:enumeration value="vnd.uplanet.cacheop" />
      <xs:enumeration value="vnd.uplanet.cacheop-wbxml" />
      <xs:enumeration value="vnd.uplanet.channel" />
      <xs:enumeration value="vnd.uplanet.channel-wbxml" />
      <xs:enumeration value="vnd.uplanet.list" />
      <xs:enumeration value="vnd.uplanet.listcmd" />
      <xs:enumeration value="vnd.uplanet.listcmd-wbxml" />
      <xs:enumeration value="vnd.uplanet.list-wbxml" />
      <xs:enumeration value="vnd.uplanet.signal" />
      <xs:enumeration value="vnd.vcx" />
      <xs:enumeration value="vnd.vectorworks" />
      <xs:enumeration value="vnd.vd-study" />
      <xs:enumeration value="vnd.vidsoft.vidconfer" />
      <xs:enumeration value="vnd.visio" />
      <xs:enumeration value="vnd.visionary" />
      <xs:enumeration value="vnd.vividence.scriptfile" />
      <xs:enumeration value="vnd.vsf" />
      <xs:enumeration value="vnd.wap.sic" />
      <xs:enumeration value="vnd.wap.slc" />
      <xs:enumeration value="vnd.wap.wbxml" />
      <xs:enumeration value="vnd.wap.wmlc" />
      <xs:enumeration value="vnd.wmlscriptc" />
      <xs:enumeration value="vnd.webturbo" />
      <xs:enumeration value="vnd.wfa.wsc" />
      <xs:enumeration value="vnd.wmc" />
      <xs:enumeration value="vnd.wmf.bootstrap" />
      <xs:enumeration value="vnd.wordperfect" />
      <xs:enumeration value="vnd.wqd" />
      <xs:enumeration value="vnd.wrq-hp3000-labelled" />
      <xs:enumeration value="vnd.wt.stf" />
      <xs:enumeration value="vnd.wv.csp+xml" />
      <xs:enumeration value="vnd.wv.csp+wbxml" />
      <xs:enumeration value="vnd.wv.ssp+xml" />
      <xs:enumeration value="vnd.xara" />
      <xs:enumeration value="vnd.xfdl" />
      <xs:enumeration value="vnd.xmi+xml" />
      <xs:enumeration value="vnd.xmpie.cpkg" />
      <xs:enumeration value="vnd.xmpie.dpkg" />
      <xs:enumeration value="vnd.xmpie.plan" />
      <xs:enumeration value="vnd.xmpie.ppkq" />

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      <xs:enumeration value="vnd.xmpie.xlim" />
      <xs:enumeration value="vnd.yamaha.hv-dic" />
      <xs:enumeration value="vnd.yamaha.hv-script" />
      <xs:enumeration value="vnd.yamaha.hv-voice" />
      <xs:enumeration value="vnd.yamaha.smaf-audio" />
      <xs:enumeration value="vnd.yamaha.smaf-phrase" />
      <xs:enumeration value="vnd.yellowriver-custom-menu" />
      <xs:enumeration value="vnd.zzazz.deck+xml" />
      <xs:enumeration value="voicexml+xml" />
      <xs:enumeration value="watcherinfo+xml" />
      <xs:enumeration value="whoispp-query" />
      <xs:enumeration value="whoispp-response" />
      <xs:enumeration value="wita" />
      <xs:enumeration value="wordperfect5.1" />
      <xs:enumeration value="wsdl+xml" />
      <xs:enumeration value="wspolicy+xml" />
      <xs:enumeration value="x400-bp" />
      <xs:enumeration value="xcap-att+xml" />
      <xs:enumeration value="xcap-caps+xml" />
      <xs:enumeration value="xcap-el+xml" />
      <xs:enumeration value="xcap-error+xml" />
      <xs:enumeration value="xcap-ns+xml" />
      <xs:enumeration value="xenc+xml" />
      <xs:enumeration value="xhtml+xml" />
      <xs:enumeration value="xml" />
      <xs:enumeration value="xml-dtd" />
      <xs:enumeration value="xml-external-parsed-entity" />
      <xs:enumeration value="xmpp+xml" />
      <xs:enumeration value="xop+xml" />
      <xs:enumeration value="xv+xml" />
      <xs:enumeration value="zip" />
    </xs:restriction>
  </xs:simpleType>
  <xs:simpleType name="audio-type">
    <xs:restriction base="xs:token">
      <xs:enumeration value="32kadpcm" />
      <xs:enumeration value="3gpp" />
      <xs:enumeration value="3gpp2" />
      <xs:enumeration value="ac3" />
      <xs:enumeration value="AMR" />
      <xs:enumeration value="AMR-WB" />
      <xs:enumeration value="amr-wb+" />
      <xs:enumeration value="asc" />
      <xs:enumeration value="basic" />
      <xs:enumeration value="BV16" />
      <xs:enumeration value="BV32" />
      <xs:enumeration value="clearmode" />
      <xs:enumeration value="CN" />
      <xs:enumeration value="DAT12" />
      <xs:enumeration value="dls" />
      <xs:enumeration value="dsr-es201108" />

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      <xs:enumeration value="dsr-es202050" />
      <xs:enumeration value="dsr-es202211" />
      <xs:enumeration value="dsr-es202212" />
      <xs:enumeration value="eac3" />
      <xs:enumeration value="DVI4" />
      <xs:enumeration value="EVRC" />
      <xs:enumeration value="EVRC0" />
      <xs:enumeration value="EVRC1" />
      <xs:enumeration value="EVRCB" />
      <xs:enumeration value="EVRCB0" />
      <xs:enumeration value="EVRCB1" />
      <xs:enumeration value="EVRC-QCP" />
      <xs:enumeration value="EVRCWB" />
      <xs:enumeration value="EVRCWB0" />
      <xs:enumeration value="EVRCWB1" />
      <xs:enumeration value="example" />
      <xs:enumeration value="G722" />
      <xs:enumeration value="G7221" />
      <xs:enumeration value="G723" />
      <xs:enumeration value="G726-16" />
      <xs:enumeration value="G726-24" />
      <xs:enumeration value="G726-32" />
      <xs:enumeration value="G726-40" />
      <xs:enumeration value="G728" />
      <xs:enumeration value="G729" />
      <xs:enumeration value="G7291" />
      <xs:enumeration value="G72D" />
      <xs:enumeration value="G72E" />
      <xs:enumeration value="GSM" />
      <xs:enumeration value="GSM-EFR" />
      <xs:enumeration value="iLBC" />
      <xs:enumeration value="L8" />
      <xs:enumeration value="L16" />
      <xs:enumeration value="L20" />
      <xs:enumeration value="L24" />
      <xs:enumeration value="LPC" />
      <xs:enumeration value="mobile-xml" />
      <xs:enumeration value="MPA" />
      <xs:enumeration value="mp4" />
      <xs:enumeration value="MP4A-LATM" />
      <xs:enumeration value="mpa-robust" />
      <xs:enumeration value="mpeg" />
      <xs:enumeration value="mpeg4-generic" />
      <xs:enumeration value="ogg" />
      <xs:enumeration value="parityfec" />
      <xs:enumeration value="PCMA" />
      <xs:enumeration value="PCMU" />
      <xs:enumeration value="prs.sid" />
      <xs:enumeration value="QCELP" />
      <xs:enumeration value="RED" />
      <xs:enumeration value="rtp-enc-aescm128" />

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      <xs:enumeration value="rtp-midi" />
      <xs:enumeration value="rtx" />
      <xs:enumeration value="SMV" />
      <xs:enumeration value="SMV0" />
      <xs:enumeration value="SMV-QCP" />
      <xs:enumeration value="sp-midi" />
      <xs:enumeration value="t140c" />
      <xs:enumeration value="t38" />
      <xs:enumeration value="telephone-event" />
      <xs:enumeration value="tone" />
      <xs:enumeration value="ulpfec" />
      <xs:enumeration value="VDVI" />
      <xs:enumeration value="VRM-WB" />
      <xs:enumeration value="vnd.3gpp.iufp" />
      <xs:enumeration value="vnd.4SB" />
      <xs:enumeration value="vnd.audiokoz" />
      <xs:enumeration value="vnd.CELP" />
      <xs:enumeration value="vnd.cisco.nse" />
      <xs:enumeration value="vnd.cmles.radio-events" />
      <xs:enumeration value="vnd.cns.anp1" />
      <xs:enumeration value="vnd.cns.inf1" />
      <xs:enumeration value="vnd.digital-winds" />
      <xs:enumeration value="vnd.dlna.adts" />
      <xs:enumeration value="vnd.dolby.mlp" />
      <xs:enumeration value="vnd.everad.plj" />
      <xs:enumeration value="vnd.hns.audio" />
      <xs:enumeration value="vnd.lucent.voice" />
      <xs:enumeration value="vnd.ms-playready.media.pya" />
      <xs:enumeration value="vnd.mokia.mobile-xmf" />
      <xs:enumeration value="vnd.nortel.vbk" />
      <xs:enumeration value="vnd.nuera.ecelp4800" />
      <xs:enumeration value="vnd.nuera.ecelp7470" />
      <xs:enumeration value="vnd.nuera.ecelp9600" />
      <xs:enumeration value="vnd.octel.sbc" />
      <xs:enumeration value="vnd.rhetorex.32kadpcm" />
      <xs:enumeration value="vnd.sealedmedia.softseal.mpeg" />
      <xs:enumeration value="vnd.vmx.cvsd" />
      <xs:enumeration value="vorbis" />
      <xs:enumeration value="vorbis.config" />
    </xs:restriction>
  </xs:simpleType>
  <xs:simpleType name="example-type">
    <xs:restriction base="xs:token" />
  </xs:simpleType>
  <xs:simpleType name="image-type">
    <xs:restriction base="xs:token">
      <xs:enumeration value="cgm" />
      <xs:enumeration value="example" />
      <xs:enumeration value="fits" />
      <xs:enumeration value="g3fax" />
      <xs:enumeration value="gif" />

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      <xs:enumeration value="ief" />
      <xs:enumeration value="jp2" />
      <xs:enumeration value="jpeg" />
      <xs:enumeration value="jpm" />
      <xs:enumeration value="jpx" />
      <xs:enumeration value="naplps" />
      <xs:enumeration value="png" />
      <xs:enumeration value="prs.btif" />
      <xs:enumeration value="prs.pti" />
      <xs:enumeration value="t38" />
      <xs:enumeration value="tiff" />
      <xs:enumeration value="tiff-fx" />
      <xs:enumeration value="vnd.adobe.photoshop" />
      <xs:enumeration value="vnd.cns.inf2" />
      <xs:enumeration value="vnd.djvu" />
      <xs:enumeration value="vnd.dwg" />
      <xs:enumeration value="vnd.dxf" />
      <xs:enumeration value="vnd.fastbidsheet" />
      <xs:enumeration value="vnd.fpx" />
      <xs:enumeration value="vnd.fst" />
      <xs:enumeration value="vnd.fujixerox.edmics-mmr" />
      <xs:enumeration value="vnd.fujixerox.edmics-rlc" />
      <xs:enumeration value="vnd.microsoft.icon" />
      <xs:enumeration value="vnd.mix" />
      <xs:enumeration value="vnd.ms-modi" />
      <xs:enumeration value="vnd.net-fpx" />
      <xs:enumeration value="vnd.sealed.png" />
      <xs:enumeration value="vnd.sealedmedia.softseal.gif" />
      <xs:enumeration value="vnd.sealedmedia.softseal.jpg" />
      <xs:enumeration value="vnd.svf" />
      <xs:enumeration value="vnd.wap.wbmp" />
      <xs:enumeration value="vnd.xiff" />
    </xs:restriction>
  </xs:simpleType>
  <xs:simpleType name="message-type">
    <xs:restriction base="xs:token">
      <xs:enumeration value="CPIM" />
      <xs:enumeration value="delivery-status" />
      <xs:enumeration value="disposition-notification" />
      <xs:enumeration value="example" />
      <xs:enumeration value="external-body" />
      <xs:enumeration value="global" />
      <xs:enumeration value="global-delivery-status" />
      <xs:enumeration value="global-disposition-notification" />
      <xs:enumeration value="global-headers" />
      <xs:enumeration value="http" />
      <xs:enumeration value="news" />
      <xs:enumeration value="partial" />
      <xs:enumeration value="rfc822" />
      <xs:enumeration value="s-http" />
      <xs:enumeration value="sip" />

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      <xs:enumeration value="sipfrag" />
      <xs:enumeration value="tracking-status" />
      <xs:enumeration value="vnd.si.simp" />
    </xs:restriction>
  </xs:simpleType>
  <xs:simpleType name="model-type">
    <xs:restriction base="xs:token">
      <xs:enumeration value="example" />
      <xs:enumeration value="iges" />
      <xs:enumeration value="mesh" />
      <xs:enumeration value="vnd.dwf" />
      <xs:enumeration value="vnd.flatland.3dml" />
      <xs:enumeration value="vnd.gdl" />
      <xs:enumeration value="vnd.gs-gdl" />
      <xs:enumeration value="vnd.gtw" />
      <xs:enumeration value="vnd.moml+xml" />
      <xs:enumeration value="vnd.mts" />
      <xs:enumeration value="vnd.parasolid.transmit.binary" />
      <xs:enumeration value="vnd.parasolid.transmit.text" />
      <xs:enumeration value="vnd.vtu" />
      <xs:enumeration value="vrml" />
    </xs:restriction>
  </xs:simpleType>
  <xs:simpleType name="multipart-type">
    <xs:restriction base="xs:token">
      <xs:enumeration value="alternative" />
      <xs:enumeration value="appledouble" />
      <xs:enumeration value="byteranges" />
      <xs:enumeration value="digest" />
      <xs:enumeration value="encrypted" />
      <xs:enumeration value="example" />
      <xs:enumeration value="form-data" />
      <xs:enumeration value="header-set" />
      <xs:enumeration value="mixed" />
      <xs:enumeration value="parallel" />
      <xs:enumeration value="related" />
      <xs:enumeration value="report" />
      <xs:enumeration value="signed" />
      <xs:enumeration value="voice-message" />
    </xs:restriction>
  </xs:simpleType>
  <xs:simpleType name="text-type">
    <xs:restriction base="xs:token">
      <xs:enumeration value="calendar" />
      <xs:enumeration value="css" />
      <xs:enumeration value="csv" />
      <xs:enumeration value="directory" />
      <xs:enumeration value="dns" />
      <xs:enumeration value="enriched" />
      <xs:enumeration value="example" />
      <xs:enumeration value="html" />

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      <xs:enumeration value="parityfec" />
      <xs:enumeration value="plain" />
      <xs:enumeration value="prs.fallenstein.rst" />
      <xs:enumeration value="prs.lines.tag" />
      <xs:enumeration value="RED" />
      <xs:enumeration value="rfc822-headers" />
      <xs:enumeration value="richtext" />
      <xs:enumeration value="rtf" />
      <xs:enumeration value="rtp-enc-aescm128" />
      <xs:enumeration value="rtx" />
      <xs:enumeration value="sgml" />
      <xs:enumeration value="t140" />
      <xs:enumeration value="tab-separated-values" />
      <xs:enumeration value="troff" />
      <xs:enumeration value="ulpfec" />
      <xs:enumeration value="uri-list" />
      <xs:enumeration value="vnd.abc" />
      <xs:enumeration value="vnd.curl" />
      <xs:enumeration value="vnd.DMClientScript" />
      <xs:enumeration value="vnd.esmertec.theme-descriptor" />
      <xs:enumeration value="vnd.fly" />
      <xs:enumeration value="vnd.fmi.flexstor" />
      <xs:enumeration value="vnd.graphviz" />
      <xs:enumeration value="vnd.in3d.3dml" />
      <xs:enumeration value="vnd.in3d.spot" />
      <xs:enumeration value="vnd.IPTC.NewsML" />
      <xs:enumeration value="vnd.IPTC.NITF" />
      <xs:enumeration value="vnd.latex-z" />
      <xs:enumeration value="vnd.motorola.reflex" />
      <xs:enumeration value="vnd.ms-mediapackage" />
      <xs:enumeration value="vnd.net2phone.commcenter.command" />
      <xs:enumeration value="vnd.si.uricatalogue" />
      <xs:enumeration value="vnd.sun.j2me.app-descriptor" />
      <xs:enumeration value="vnd.trolltech.linguist" />
      <xs:enumeration value="vnd.wap.si" />
      <xs:enumeration value="vnd.wap.sl" />
      <xs:enumeration value="vnd.wap.wml" />
      <xs:enumeration value="vnd.wap.wmlscript" />
      <xs:enumeration value="xml" />
      <xs:enumeration value="xml-external-parsed-entity" />
    </xs:restriction>
  </xs:simpleType>
  <xs:simpleType name="video-type">
    <xs:restriction base="xs:token">
      <xs:enumeration value="3gpp" />
      <xs:enumeration value="3gpp2" />
      <xs:enumeration value="3gpp-tt" />
      <xs:enumeration value="BMPEG" />
      <xs:enumeration value="BT656" />
      <xs:enumeration value="CelB" />
      <xs:enumeration value="DV" />

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      <xs:enumeration value="example" />
      <xs:enumeration value="H261" />
      <xs:enumeration value="H263" />
      <xs:enumeration value="H263-1998" />
      <xs:enumeration value="H263-2000" />
      <xs:enumeration value="H264" />
      <xs:enumeration value="JPEG" />
      <xs:enumeration value="MJ2" />
      <xs:enumeration value="MP1S" />
      <xs:enumeration value="MP2P" />
      <xs:enumeration value="MP2T" />
      <xs:enumeration value="mp4" />
      <xs:enumeration value="MP4V-ES" />
      <xs:enumeration value="MPV" />
      <xs:enumeration value="mpeg" />
      <xs:enumeration value="mpeg4-generic" />
      <xs:enumeration value="nv" />
      <xs:enumeration value="ogg" />
      <xs:enumeration value="parityfec" />
      <xs:enumeration value="pointer" />
      <xs:enumeration value="quicktime" />
      <xs:enumeration value="raw" />
      <xs:enumeration value="rtp-enc-aescm128" />
      <xs:enumeration value="rtx" />
      <xs:enumeration value="SMTPE292M" />
      <xs:enumeration value="ulpfec" />
      <xs:enumeration value="vc1" />
      <xs:enumeration value="vnd.CCTV" />
      <xs:enumeration value="vnd.dlna.mpeg-tts" />
      <xs:enumeration value="vnd.fvt" />
      <xs:enumeration value="vnd.hns.video" />
      <xs:enumeration value="vnd.iptvforum.1dparityfec-1010" />
      <xs:enumeration value="vnd.iptvforum.1dparityfec-2005" />
      <xs:enumeration value="vnd.iptvforum.2dparityfec-1010" />
      <xs:enumeration value="vnd.iptvforum.2dparityfec-2005" />
      <xs:enumeration value="vnd.iptvforum.ttsavc" />
      <xs:enumeration value="vnd.iptvforum.ttsmpeg2" />
      <xs:enumeration value="vnd.motorola.video" />
      <xs:enumeration value="vnd.motorola.videop" />
      <xs:enumeration value="vnd.mpegurl" />
      <xs:enumeration value="vnd.ms-playready.mediapyv" />
      <xs:enumeration value="vnd.nokia.interleaved-multimedia" />
      <xs:enumeration value="vnd.nokia.videovoip" />
      <xs:enumeration value="vnd.objectvideo" />
      <xs:enumeration value="vnd.sealed.mpeg1" />
      <xs:enumeration value="vnd.sealed.mpeg4" />
      <xs:enumeration value="vnd.sealed.swf" />
      <xs:enumeration value="vnd.sealedmedia.softseal.mov" />
      <xs:enumeration value="vnd.vivo" />
    </xs:restriction>
  </xs:simpleType>

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  <xs:group name="super-types">
    <xs:choice>
      <xs:element name="application" type="application-type" />
      <xs:element name="audio" type="audio-type" />
      <xs:element name="example" type="example-type" />
      <xs:element name="image" type="image-type" />
      <xs:element name="message" type="message-type" />
      <xs:element name="model" type="model-type" />
      <xs:element name="multipa t" type="multipart-type" />
      <xs:element name="text" type="text-type" />
      <xs:element name="video" type="video-type" />
    </xs:choice></xs:group><xs:complexType name="mime-type">
    <xs:group ref="super-types" /></xs:complexType></xs:schema>

6. MML Schema
<?xml version="1.0" encoding="utf-8" ?><xs:schema 
  xmlns:xfm="http://www.w3.org/2002/xforms"
  elementFormDefault="qualified" version="1.1"
  xmlns:xs="http://www.w3.org/2001/XMLSchema"><xs:import
  schemaLocation="http://www.w3.org/MarkUp/Forms/2002/XForms-Schema.xsd"
  namespace="http://www.w3.org/2002/xforms" />
  <xs:include schemaLocation="http://mailmarkup.org/mime.xsd" />
  <xs:element name="mail">
    <xs:complexType>
      <xs:sequence>
        <xs:element maxOccurs="unbounded" ref="session" />
      </xs:sequence><xs:attribute ref="mail-type" use="required" />
      <xs:attribute fixed="http://mailmarkup.org/"
	  name="targetNamespace" use="required" />
    </xs:complexType>
  </xs:element>
  <xs:attribute fixed="application/mail" name="mail-type" />
  <xs:element name="session">
    <xs:complexType>
      <xs:sequence>
        <xs:element ref="address" />
        <xs:element minOccurs="0" ref="attachments" />
        <xs:element ref="subject" />
        <xs:element minOccurs="0" ref="presentation" />
        <xs:choice>
          <xs:element ref="source" />
          <xs:element ref="plain-text" />
          <xs:element ref="markup" />
        </xs:choice>
      </xs:sequence>
      <xs:attribute ref="time-stamp" use="required" />
      <xs:attribute default="en" ref="language" use="optional" />
    </xs:complexType>
  </xs:element>
  <xs:attribute name="time-stamp">
    <xs:simpleType>

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      <xs:restriction base="xs:dateTime" />
    </xs:simpleType>
  </xs:attribute>
  <xs:attribute name="language">
    <xs:simpleType>
      <xs:restriction base="xs:language" />
    </xs:simpleType>
  </xs:attribute>
  <xs:element name="address">
    <xs:complexType>
      <xs:sequence>
        <xs:element ref="to" />
        <xs:element minOccurs="0" ref="copy" />
        <xs:element minOccurs="0" ref="blind-copy" />
        <xs:element ref="from" />
        <xs:element ref="reply-to" />
      </xs:sequence>
    </xs:complexType>
  </xs:element>
  <xs:element name="to">
    <xs:complexType>
      <xs:sequence>
        <xs:element maxOccurs="unbounded" ref="agent" />
      </xs:sequence>
    </xs:complexType>
  </xs:element>
  <xs:element name="copy">
    <xs:complexType>
      <xs:sequence>
        <xs:element maxOccurs="unbounded" ref="agent" />
      </xs:sequence>
    </xs:complexType>
  </xs:element>
  <xs:element name="blind-copy">
    <xs:complexType>
      <xs:sequence>
        <xs:element maxOccurs="unbounded" ref="agent" />
      </xs:sequence>
    </xs:complexType>
  </xs:element>
  <xs:element name="from">
    <xs:complexType>
      <xs:sequence>
        <xs:element ref="agent" />
      </xs:sequence>
    </xs:complexType>
  </xs:element>
  <xs:element name="reply-to">
    <xs:complexType>
      <xs:sequence>
        <xs:element ref="reply-address" />

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        <xs:element minOccurs="0" ref="alias" />
        <xs:element minOccurs="0" ref="public-key" />
      </xs:sequence>
    </xs:complexType>
  </xs:element>
  <xs:element name="agent">
    <xs:complexType>
      <xs:sequence>
        <xs:element ref="mail-address" />
        <xs:element minOccurs="0" ref="alias" />
        <xs:element minOccurs="0" ref="public-key" />
      </xs:sequence>
    </xs:complexType>
  </xs:element>
  <xs:element name="mail-address">
    <xs:simpleType>
      <xs:restriction base="xs:anyURI"><xs:pattern
     value="\c+(\.\c)*@\c+(\.\c)*(\.[a-z]{2,3})|([a-z]{2}\.[a-z]{2})" />
      </xs:restriction>
    </xs:simpleType>
  </xs:element>
  <xs:element name="reply-address">
    <xs:simpleType>
      <xs:restriction base="xs:anyURI"><xs:pattern
     value="\c+(\.\c)*@\c+(\.\c)*(\.[a-z]{2,3})|([a-z]{2}\.[a-z]{2})" />
        <xs:pattern value="no-reply" />
      </xs:restriction>
    </xs:simpleType>
  </xs:element>
  <xs:element name="alias">
    <xs:simpleType>
      <xs:restriction base="xs:token" />
    </xs:simpleType>
  </xs:element>
  <xs:element name="public-key">
    <xs:simpleType>
      <xs:restriction base="xs:token" />
    </xs:simpleType>
  </xs:element>
  <xs:element name="attachments">
    <xs:complexType>
      <xs:choice maxOccurs="unbounded">
        <xs:element ref="collection" />
        <xs:element ref="file" />
      </xs:choice>
    </xs:complexType>
  </xs:element>
  <xs:element name="collection">
    <xs:complexType>
      <xs:sequence>
        <xs:element ref="collection-name" />

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        <xs:element maxOccurs="unbounded" ref="collection-file" />
        <xs:element minOccurs="0" ref="collection-type" />
        <xs:element ref="collection-description" />
      </xs:sequence>
    </xs:complexType>
  </xs:element>
  <xs:element name="collection-name">
    <xs:simpleType>
      <xs:restriction base="xs:normalizedString" />
    </xs:simpleType>
  </xs:element>
  <xs:element name="collection-file">
    <xs:simpleType>
      <xs:restriction base="xs:NCName" />
    </xs:simpleType>
  </xs:element>
  <xs:element name="collection-type" type="mime-type" />
  <xs:element name="collection-description">
    <xs:simpleType>
      <xs:restriction base="xs:normalizedString" />
    </xs:simpleType>
  </xs:element>
  <xs:element name="file">
    <xs:complexType>
      <xs:sequence>
        <xs:element ref="file-name" />
        <xs:element ref="file-type" />
        <xs:element ref="file-description" />
      </xs:sequence>
    </xs:complexType>
  </xs:element>
  <xs:element name="file-name">
    <xs:simpleType>
      <xs:restriction base="xs:NCName">
        <xs:pattern value="\c+(\.\c+)+" />
      </xs:restriction>
    </xs:simpleType>
  </xs:element>
  <xs:element name="file-type" type="mime-type" />
  <xs:element name="file-description">
    <xs:simpleType>
      <xs:restriction base="xs:normalizedString" />
    </xs:simpleType>
  </xs:element>
  <xs:element name="subject">
    <xs:simpleType>
      <xs:restriction base="xs:normalizedString" />
    </xs:simpleType>
  </xs:element>
  <xs:element name="presentation">
    <xs:complexType>

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      <xs:sequence maxOccurs="unbounded">
        <xs:element ref="stylesheet" />
      </xs:sequence>
    </xs:complexType>
  </xs:element>
  <xs:element name="stylesheet">
    <xs:complexType>
      <xs:sequence>
        <xs:element ref="style-uri" />
        <xs:element ref="style-namespace" />
      </xs:sequence>
      <xs:attribute ref="style-type" use="required" />
    </xs:complexType>
  </xs:element>
  <xs:attribute name="style-type">
    <xs:simpleType>
      <xs:restriction base="xs:token">
        <xs:enumeration value="application/xml" />
        <xs:enumeration value="text/xsl" />
        <xs:enumeration value="text/css" />
      </xs:restriction>
    </xs:simpleType>
  </xs:attribute>
  <xs:element name="style-uri">
    <xs:simpleType>
      <xs:restriction base="xs:anyURI" />
    </xs:simpleType>
  </xs:element>
  <xs:element name="style-namespace">
    <xs:simpleType>
      <xs:restriction base="xs:NCName">
        <xs:pattern value="[a-zA-Z0-9]+" />
      </xs:restriction>
    </xs:simpleType>
  </xs:element>
  <xs:element name="source">
    <xs:complexType>
      <xs:sequence>
        <xs:element ref="source-uri" />
        <xs:element ref="source-type" />
      </xs:sequence>
    </xs:complexType>
  </xs:element>
  <xs:element name="source-uri">
    <xs:simpleType>
      <xs:restriction base="xs:anyURI" />
    </xs:simpleType>
  </xs:element>
  <xs:element name="source-type" type="mime-type" />
  <xs:element name="plain-text">
    <xs:simpleType>

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      <xs:restriction base="xs:string" />
    </xs:simpleType>
  </xs:element>
  <xs:element name="markup">
    <xs:complexType>
      <xs:sequence>
        <xs:choice maxOccurs="unbounded">
          <xs:group ref="complex-blocks" />
          <xs:group ref="simple-blocks" />
        </xs:choice>
      </xs:sequence>
    </xs:complexType></xs:element>
  <xs:attributeGroup name="core-attrs">
    <xs:attribute ref="id" use="optional" />
    <xs:attribute ref="style" use="optional" />
    <xs:attribute ref="title" use="optional" />
    <xs:attribute ref="role" use="optional" />
  </xs:attributeGroup>
  <xs:attributeGroup name="core-attrs-uri">
    <xs:attribute ref="id" use="optional" />
    <xs:attribute ref="style" use="optional" />
    <xs:attribute ref="title" use="optional" />
    <xs:attribute ref="role" use="optional" />
    <xs:attribute ref="uri" use="optional" />
  </xs:attributeGroup>
  <xs:attributeGroup name="inter-attrs">
    <xs:attribute default="tl" ref="direction" use="optional" />
    <xs:attribute default="horizontal" ref="orientation"
      use="optional" />
    <xs:attribute default="standard" ref="wrap" use="optional" />
    <xs:attribute default="en" ref="section-language" use="optional" />
  </xs:attributeGroup>
  <xs:attributeGroup name="cell-attrs">
    <xs:attribute default="1" ref="span-column" use="optional" />
    <xs:attribute default="1" ref="span-row" use="optional" />
  </xs:attributeGroup>
  <xs:attribute name="id">
    <xs:simpleType>
      <xs:restriction base="xs:ID">
        <xs:pattern value="[a-zA-Z0-9]+" />
      </xs:restriction>
    </xs:simpleType>
  </xs:attribute>
  <xs:attribute name="style">
    <xs:simpleType>
      <xs:restriction base="xs:token">
        <xs:pattern value="[a-zA-Z0-9]+:[a-zA-Z0-9]+" />
      </xs:restriction>
    </xs:simpleType>
  </xs:attribute>
  <xs:attribute name="title">

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    <xs:simpleType>
      <xs:restriction base="xs:normalizedString" />
    </xs:simpleType>
  </xs:attribute>
  <xs:attribute name="role">
    <xs:simpleType>
      <xs:restriction base="xs:token" />
    </xs:simpleType>
  </xs:attribute>
  <xs:attribute name="uri">
    <xs:simpleType>
      <xs:restriction base="xs:anyURI" />
    </xs:simpleType>
  </xs:attribute>
  <xs:attribute name="direction">
    <xs:simpleType>
      <xs:restriction base="xs:token">
        <xs:enumeration value="tl" />
        <xs:enumeration value="br" />
      </xs:restriction>
    </xs:simpleType>
  </xs:attribute>
  <xs:attribute name="orientation">
    <xs:simpleType>
      <xs:restriction base="xs:token">
        <xs:enumeration value="horizontal" />
        <xs:enumeration value="vertical" />
      </xs:restriction>
    </xs:simpleType>
  </xs:attribute>
  <xs:attribute name="wrap">
    <xs:simpleType>
      <xs:restriction base="xs:token">
        <xs:enumeration value="standard" />
        <xs:enumeration value="reverse" />
        <xs:enumeration value="none" />
      </xs:restriction>
    </xs:simpleType>
  </xs:attribute>
  <xs:attribute name="section-language">
    <xs:simpleType>
      <xs:restriction base="xs:language" />
    </xs:simpleType>
  </xs:attribute>
  <xs:attribute name="refer">
    <xs:simpleType>
      <xs:restriction base="xs:IDREF" />
    </xs:simpleType>
  </xs:attribute>
  <xs:attribute name="span-column">
    <xs:simpleType>

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      <xs:restriction base="xs:positiveInteger" />
    </xs:simpleType>
  </xs:attribute>
  <xs:attribute name="span-row">
    <xs:simpleType>
      <xs:restriction base="xs:positiveInteger" />
    </xs:simpleType>
  </xs:attribute>
  <xs:attribute name="scope">
    <xs:simpleType>
      <xs:restriction base="xs:token">
        <xs:enumeration value="column" />
        <xs:enumeration value="row" />
        <xs:enumeration value="group-column" />
        <xs:enumeration value="group-row" />
      </xs:restriction>
    </xs:simpleType>
  </xs:attribute>
  <xs:attribute name="long-form">
    <xs:simpleType>
      <xs:restriction base="xs:token" />
    </xs:simpleType>
  </xs:attribute>
  <xs:group name="complex-blocks">
    <xs:choice>
      <xs:group ref="list-group" />
      <xs:element ref="table" />
      <xs:element ref="section" />
      <xs:element ref="form" />
    </xs:choice>
  </xs:group>
  <xs:group name="simple-blocks">
    <xs:choice>
      <xs:element ref="block-code" />
      <xs:element ref="block-quote" />
      <xs:element ref="citation" />
      <xs:element ref="heading" />
      <xs:element ref="object" />
      <xs:element ref="paragraph" />
      <xs:element ref="separator" />
    </xs:choice>
  </xs:group>
  <xs:complexType name="simple-blocks-type" mixed="true">
    <xs:group minOccurs="0" maxOccurs="unbounded" ref="inline" />
    <xs:attributeGroup ref="core-attrs" />
    <xs:attributeGroup ref="inter-attrs" />
  </xs:complexType>
  <xs:group name="inline">
    <xs:choice>
      <xs:group ref="xfm:Form.Controls" />
      <xs:element ref="short" />

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      <xs:element ref="button" />
      <xs:element ref="cite" />
      <xs:element ref="emphasis" />
      <xs:element ref="identifier" />
      <xs:element ref="quote" />
      <xs:element ref="format" />
      <xs:element ref="strong" />
      <xs:element ref="title" />
    </xs:choice>
  </xs:group>
  <xs:group name="object-group">
    <xs:sequence>
      <xs:element ref="object-text" />
      <xs:element ref="object-uri" />
      <xs:element ref="object-type" />
      <xs:group minOccurs="0" maxOccurs="unbounded" ref="inline" />
    </xs:sequence>
  </xs:group>
  <xs:complexType name="inline-type">
    <xs:simpleContent>
      <xs:extension base="xs:string">
        <xs:attributeGroup ref="core-attrs-uri" />
      </xs:extension>
    </xs:simpleContent>
  </xs:complexType>
  <xs:complexType name="format-type" mixed="true">
    <xs:sequence>
      <xs:element minOccurs="0" maxOccurs="unbounded" ref="format" />
    </xs:sequence>
    <xs:attributeGroup ref="core-attrs-uri" />
  </xs:complexType>
  <xs:group name="list-group">
    <xs:choice>
      <xs:element ref="define-list" />
      <xs:element ref="navigation-list" />
      <xs:element ref="order-list" />
      <xs:element ref="unorder-list" />
    </xs:choice>
  </xs:group>
  <xs:complexType name="nesting-block">
    <xs:choice maxOccurs="unbounded">
      <xs:group ref="complex-blocks" />
      <xs:group ref="simple-blocks" />
    </xs:choice>
  </xs:complexType>
  <xs:element name="define-list">
    <xs:complexType>
      <xs:sequence>
        <xs:element maxOccurs="unbounded" ref="define-item" />
      </xs:sequence>
      <xs:attributeGroup ref="core-attrs" />

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    </xs:complexType>
  </xs:element>
  <xs:element name="define-item">
    <xs:complexType>
      <xs:sequence>
        <xs:element maxOccurs="unbounded" ref="define-term" />
        <xs:element maxOccurs="unbounded" ref="definition" />
      </xs:sequence>
      <xs:attributeGroup ref="core-attrs" />
    </xs:complexType>
  </xs:element>
  <xs:element name="define-term">
    <xs:complexType>
      <xs:simpleContent>
        <xs:extension base="xs:normalizedString">
          <xs:attributeGroup ref="core-attrs-uri" />
          <xs:attributeGroup ref="inter-attrs" />
        </xs:extension>
      </xs:simpleContent>
    </xs:complexType>
  </xs:element>
  <xs:element name="definition">
    <xs:complexType mixed="true">
      <xs:group minOccurs="0" maxOccurs="unbounded" ref="inline" />
      <xs:attributeGroup ref="core-attrs" />
      <xs:attributeGroup ref="inter-attrs" />
    </xs:complexType>
  </xs:element>
  <xs:element name="navigation-list">
    <xs:complexType>
      <xs:sequence>
        <xs:choice minOccurs="0">
          <xs:element ref="heading" />
          <xs:element ref="identifier" />
        </xs:choice>
        <xs:element maxOccurs="unbounded" ref="navigation-item" />
      </xs:sequence>
      <xs:attributeGroup ref="core-attrs" />
    </xs:complexType>
  </xs:element>
  <xs:element name="navigation-item">
    <xs:complexType>
      <xs:choice>
        <xs:element ref="navigation-object" />
        <xs:element ref="navigation-text" />
      </xs:choice>
      <xs:attributeGroup ref="core-attrs" />
      <xs:attribute ref="uri" use="required" />
    </xs:complexType>
  </xs:element>
  <xs:element name="navigation-object">

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    <xs:complexType>
      <xs:sequence>
        <xs:element ref="object-text" />
        <xs:element ref="object-uri" />
        <xs:element ref="object-type" />
      </xs:sequence>
      <xs:attributeGroup ref="inter-attrs" />
      <xs:attributeGroup ref="core-attrs" />
    </xs:complexType>
  </xs:element>
  <xs:element name="object-text">
    <xs:simpleType>
      <xs:restriction base="xs:normalizedString" />
    </xs:simpleType>
  </xs:element>
  <xs:element name="object-uri">
    <xs:simpleType>
      <xs:restriction base="xs:anyURI" />
    </xs:simpleType>
  </xs:element>
  <xs:element name="object-type" type="mime-type" />
  <xs:element name="navigation-text">
    <xs:complexType>
      <xs:simpleContent>
        <xs:extension base="xs:string">
          <xs:attributeGroup ref="inter-attrs" />
          <xs:attributeGroup ref="core-attrs" />
        </xs:extension>
      </xs:simpleContent>
    </xs:complexType>
  </xs:element>
  <xs:element name="order-list">
    <xs:complexType>
      <xs:sequence>
        <xs:choice minOccurs="0">
          <xs:element ref="heading" />
          <xs:element ref="identifier" />
        </xs:choice>
        <xs:element maxOccurs="unbounded" ref="list-item" />
      </xs:sequence>
      <xs:attributeGroup ref="core-attrs" />
    </xs:complexType>
  </xs:element>
  <xs:element name="unorder-list">
    <xs:complexType>
      <xs:sequence>
        <xs:choice minOccurs="0">
          <xs:element ref="heading" />
          <xs:element ref="identifier" />
        </xs:choice>
        <xs:element maxOccurs="unbounded" ref="list-item" />

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      </xs:sequence>
      <xs:attributeGroup ref="core-attrs" />
    </xs:complexType>
  </xs:element>
  <xs:element name="list-item">
    <xs:complexType mixed="true">
      <xs:choice>
        <xs:group ref="simple-blocks" />
        <xs:group maxOccurs="unbounded" ref="inline" />
      </xs:choice>
      <xs:attributeGroup ref="core-attrs" />
      <xs:attributeGroup ref="inter-attrs" />
    </xs:complexType>
  </xs:element>
  <xs:element name="form">
    <xs:complexType>
      <xs:sequence>
        <xs:element ref="xfm:model" />
        <xs:element ref="form-body" />
      </xs:sequence>
    </xs:complexType>
  </xs:element>
  <xs:element name="form-body">
    <xs:complexType>
      <xs:choice maxOccurs="unbounded">
        <xs:group ref="list-group" />
        <xs:group ref="simple-blocks" />
        <xs:group ref="xfm:UI.Common" />
        <xs:element ref="table" />
      </xs:choice>
    </xs:complexType>
  </xs:element>
  <xs:element name="table">
    <xs:complexType>
      <xs:sequence>
        <xs:element minOccurs="0" ref="head-row" />
        <xs:element maxOccurs="unbounded" ref="table-row" />
      </xs:sequence>
      <xs:attributeGroup ref="core-attrs" />
    </xs:complexType>
  </xs:element>
  <xs:element name="head-row">
    <xs:complexType>
      <xs:sequence>
        <xs:element maxOccurs="unbounded" ref="head-cell" />
      </xs:sequence>
      <xs:attributeGroup ref="core-attrs" />
    </xs:complexType>
  </xs:element>
  <xs:element name="head-cell">
    <xs:complexType mixed="true">

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      <xs:choice>
        <xs:group ref="simple-blocks" />
        <xs:group maxOccurs="unbounded" ref="inline" />
      </xs:choice>
      <xs:attribute default="column" ref="scope" use="optional" />
      <xs:attributeGroup ref="cell-attrs" />
      <xs:attributeGroup ref="core-attrs" />
      <xs:attributeGroup ref="inter-attrs" />
    </xs:complexType>
  </xs:element>
  <xs:element name="table-row">
    <xs:complexType>
      <xs:choice maxOccurs="unbounded">
        <xs:element ref="head-cell" />
        <xs:element ref="table-cell" />
      </xs:choice>
      <xs:attributeGroup ref="core-attrs" />
    </xs:complexType>
  </xs:element>
  <xs:element name="table-cell">
    <xs:complexType mixed="true">
      <xs:choice>
        <xs:group ref="simple-blocks" />
        <xs:group maxOccurs="unbounded" ref="inline" />
      </xs:choice>
      <xs:attributeGroup ref="cell-attrs" />
      <xs:attributeGroup ref="core-attrs" />
      <xs:attributeGroup ref="inter-attrs" />
    </xs:complexType>
  </xs:element>
  <xs:element name="section">
    <xs:complexType>
      <xs:complexContent mixed="false">
        <xs:extension base="nesting-block">
          <xs:attributeGroup ref="core-attrs" />
        </xs:extension>
      </xs:complexContent>
    </xs:complexType>
  </xs:element>
  <xs:element name="block-code" type="simple-blocks-type" />
  <xs:element name="block-quote" type="simple-blocks-type" />
  <xs:element name="citation">
    <xs:complexType mixed="true">
      <xs:group minOccurs="0" maxOccurs="unbounded" ref="inline" />
      <xs:attribute ref="id" use="required" />
      <xs:attribute ref="style" use="optional" />
      <xs:attribute ref="title" use="optional" />
      <xs:attribute ref="role" use="optional" />
      <xs:attributeGroup ref="inter-attrs" />
    </xs:complexType>
  </xs:element>

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  <xs:element name="heading" type="simple-blocks-type" />
  <xs:element name="object">
    <xs:complexType>
      <xs:group ref="object-group" />
      <xs:attributeGroup ref="inter-attrs" />
      <xs:attributeGroup ref="core-attrs" />
    </xs:complexType>
  </xs:element>
  <xs:element name="paragraph" type="simple-blocks-type" />
  <xs:element name="separator" type="simple-blocks-type" />
  <xs:element name="short">
    <xs:complexType>
      <xs:simpleContent>
        <xs:extension base="xs:string">
          <xs:attribute ref="long-form" use="required" />
          <xs:attributeGroup ref="core-attrs-uri" />
        </xs:extension>
      </xs:simpleContent>
    </xs:complexType>
  </xs:element>
  <xs:element name="button">
    <xs:complexType>
      <xs:simpleContent>
        <xs:extension base="xs:string">
          <xs:attribute ref="refer" use="optional" />
          <xs:attributeGroup ref="core-attrs-uri" />
        </xs:extension>
      </xs:simpleContent>
    </xs:complexType>
  </xs:element>
  <xs:element name="cite">
    <xs:complexType>
      <xs:simpleContent>
        <xs:extension base="xs:string">
          <xs:attribute ref="refer" use="required" />
          <xs:attributeGroup ref="core-attrs" />
        </xs:extension>
      </xs:simpleContent>
    </xs:complexType>
  </xs:element>
  <xs:element name="emphasis" type="inline-type" />
  <xs:element name="identifier">
    <xs:complexType>
      <xs:simpleContent>
        <xs:extension base="xs:string">
          <xs:attribute ref="refer" use="required" />
          <xs:attributeGroup ref="core-attrs-uri" />
        </xs:extension>
      </xs:simpleContent>
    </xs:complexType>
  </xs:element>

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  <xs:element name="quote" type="inline-type" />
  <xs:element name="format" type="format-type" />
  <xs:element name="strong" type="inline-type" />
  <xs:element name="title" type="inline-type" />
  <xs:annotation>
    <xs:documentation>
			Written by Austin Cheney on 12 October 2007.
		</xs:documentation>
  </xs:annotation>
</xs:schema>

7. MML Schema Documentation
   This section is intended to provide a description of the language
   along with justifications for certain conventions used.  This section
   is informational only.  All processing declarations are stated in
   section 4. Processor Roles and section 5. MML Schema.

   If an element is followed by "0" it MAY occur 0 or 1 time.  If an
   element is followed by "+" it MUST occur once, but it MAY occur more
   than once.  If an item is followed by "0+" it MAY occur 0 or more
   times.  If an element does not have these descriptors it MUST occur
   once and only once.  Attributes MAY be followed by "0", which
   indicates the attribute in concern is optional.  Attributes MUST NOT
   occur more than once in any element.

   Those elements noted as (XForms) are defined by the XForms
   specification and not this document.  For more information see
   section 3.2. XForms and 4.1.8. Local Processing.  These elements must
   be processed in accordance with the XForms schema.

7.1. MIME Type Usage and mime.xsd
   MIME types MUST be stored in the mime.xsd document, which is merely a
   catalogue of all IANA registered MIME types at the time of this
   writing.  The information stored in mime.xsd is used in the MML
   schema through the use of the "mime-type" schema complex type.

   Elements based upon the "mime-type" element type are allowed only one
   of nine possible child elements.  These child elements each represent
   a IANA registered content type.  The values for those child elements
   MUST be a MIME sub-type that exists in the local mime.xsd file.  The
   child elements are:
      * <application> or <audio> or <example> or <image> or <message> or
        <model> or <multipart> or <text> or <video>

7.2. MML Header Documentation
   The code described in this section exists in MML documents without
   regard to how the message is formatted.  For more information about
   the message body see section 7.2.2. <session> Tag and section 7.3.
   <markup> Element Documentation.



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7.2.1. Root Element
   The root element of MML is the tag <mail>.  This tag serves only
   three purposes.  First, the tag establishes the document as a MML
   document conforming to the mail.xsd schema.  Second, the tag serves
   as a container of <session> tags.  Third, the tag establishes
   important namespace information.  The root element serves no further
   purpose.

7.2.2. <session> Tag
   The session tag contains all information to represent an instance of
   communication including markup and header information.  A session
   tag's child tags are as follows:
      * <address>
      * <attachments> 0
      * <subject>
      * <presentation> 0
      * <source> or <markup> or <plain-text>

   The session tag's attributes:
      * time-stamp
      * language (optional)

   The session tag allows three methods of communicating the message
   body.  The source method allows a session author to send an external
   resource as the message body.  Please see section 7.2.26 <source>
   Tag.  The plain-text method allows a session author to communicate
   using only text characters and whitespace.  Please see section
   7.2.29. <plain-text> Tag.  The markup method allows a section author
   to use MML markup to describe the data.  Please see section 7.2.30.
   <markup> Tag and section 7.3. <markup> Organization of Types and
   Groups and 7.4. <markup> Attributes and 7.5. <markup> Elements.

   The time-stamp attribute is described in section 4.1.6. Session
   Time-stamp.  The optional language attribute allows a session author
   to describe the majority language of the document.  The default value
   is "EN".

7.2.3. <address> Tag
   The address tag is a high level tag designed to store child tags
   containing email address information.  The child tags are:
      * <to>
      * <copy> 0
      * <blind-copy> 0
      * <reply-to>
      * <from>







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7.2.4. <to>, <copy>, <blind-Copy>, and <from> Tags
   The <to>, <copy>, <blind-copy>, and <from> are identical in their
   syntax.  They only differ in their use by the MML processor.  These
   tags have only one child, but that child may occur as many times as
   needed.  The <from> tag differs in that its child MUST occur once.
   The child tag is:
      * <agent> +

7.2.5. <agent> Tag
   The <agent> tag represents a single email address plus some optional
   meta-data.  The child tags are:
      * <mail-address>
      * <alias> 0
      * <public-key> 0

7.2.6. <mail-address> Tag
   The <mail-address> tag must contain an email address.  MML does not
   care if the address supplied is valid or not so long as it is a
   well-formed email address.  A regular expression pattern is used to
   define what qualifies as a well-formed email address.  Any content
   that does not conform to this pattern will cause the document to not
   validate.

7.2.7. <alias> Tag
   The <alias> tag is used to supply a label for a corresponding email
   address.  An example is to use and refer to a target destination by a
   person's name supplied as content to the <alias> instead of having to
   memorize an email address.

7.2.8. <public-key> Tag
   The <public-key> tag is intended to store text characters that
   represent a hashed public-key for asymmetric encryption.

7.2.9. <reply-to> Tag
   The <reply-to> tag is identical to the <from> tag except that it has
   a child of <reply-address> instead of <mail-address>.  This tag is
   used to set an address for deflecting email replys from the address
   used to send the email or to establish an alternate destination for
   receiving replies.  The <reply-to> tag child tags are:
      * <reply-address>
      * <alias> 0
      * <public-key> 0

7.2.10. <reply-address> Tag
   The <reply-address> tag is identical to the <mail-address> tag except
   that it MAY also take a literal value of "no-reply".






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7.2.11. <attachments> Tag
   The <attachments> tag is a high level tag for specifying file to be
   attached to the document.  Attached files are not intended for
   processing in the message body.  This tag has two children which may
   occur as many times as needed.  At a minimum only one of these child
   elements must occur:
      * <collection> + and/or <file> +

7.2.12 <collection> Tag
   The <collection> tag is intended to serve as a collection of multiple
   files of the same specified type.  This tag has four child tags:
      * <collection-name>
      * <collection-file> +
      * <collection-type> 0
      * <collection-description>

7.2.13. <collection-name> Tag
   <collection-name> tag is a required child of <collection>.  This may
   be any string value on a single line.  The intent of this tag is to
   provide a simple name or label for the attached collection.

7.2.14. <collection-file> Tag
   <collection-file> tag stores the file name of a particular file in a
   collection.  This tag MUST exist for each file that is to exist in
   the collection.

7.2.15. <collection-type> Tag
   The <collection-type> tag is a "mime-type" complex-type tag as
   specified in mime.xsd.  The value provided for this tag MUST
   represent every file in the collection.  This tag is optional.  If
   this tag is not present the files present in the collection MUST NOT
   be processed by the MML processor.  See section 4.1.11. Attachments
   for information on processing requirements.  Please see section 7.1.
   MIME Type Usage and mime.xsd for information about the specified type
   "mime-type".  MML processors are not REQUIRED to process attached
   collections.

7.2.16. <collection-description> Tag
   This required tag exists to specify a description of the collection.
   Examples of content for this tag MAY be examples of intended use,
   explanations, file ownership, origin information, and so forth.

7.2.17. <file> Tag
   The <file> tag is intended to serve as a single attached file.  This
   tag has three child tags:
      * <file-name>
      * <file-type>
      * <file-description>




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7.2.18. <file-name> Tag
   <file-name> tag is a required child of <file>.  The value for this
   tag MUST be a non-colonized name.  This tag represents the name of
   the file being attached.

7.2.19. <file-type> Tag
   This tag is of type "mime-type".  The attached file MUST be processed
   according to the value supplied in this tag, or it MUST NOT be
   processed by a MML processor.  MML processors are not required to
   process attached files.

7.2.20. <file-description> Tag
   This tag allows a session author to enter any normalized string value
   that describes the attached file.  This tag is REQUIRED.

7.2.21. <subject> Tag
   The <