Registration of mail and MIME header fields Nine by Nine
UK GK-IETF@ninebynine.org http://www.ninebynine.net/
Stockholm University/KTH
Forum 100 Kista S-164 40 Sweden +46-8-16 16 67 +46-8-783 08 29 jpalme@dsv.su.se
Application message header fields email headers RFC2822 MIME registration IANA This document defines the initial IANA registration for permanent mail and MIME message header fields, per [[[RFC XXXX (xref target="msghdr-registry" /)]]]. Please send comments to <ietf-822@imc.org>. To subscribe to this list, send a message with the body 'subscribe' to <ietf-822-request@imc.org>.
This document defines IANA registration for a number of mail message and MIME header fields, per Registration procedures for message header fields. The main body of this document is automatically generated from RDF/N3 data. Some experimental HTML registry pages have been prepared from the same data, and can be found at .
Section contains the templates for initial registration of mail message header fields. Section contains templates for initial registration of MIME header fields.
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 . [[[Editorial comments and questions about outstanding issues are provided in triple brackets like this. These working comments should be resolved and removed prior to final publication.]]]
Header field registry entries are summarized in tabular form for convenience of reference, and presented in full in the following sections.
Message date and time Mail standard IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2822 (section 3.6.1) Specifies the date and time at which the creator of the message indicated that the message was complete and ready to enter the mail delivery system. Defined as standard by RFC 822.
Mailbox of message author Mail standard IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2822 (section 3.6.2) Specifies the author(s) of the message, that is, the mailbox(es) of the person(s) or system(s) responsible for the writing of the message. Defined as standard by RFC 822.
Mailbox of message sender Mail standard IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2822 (section 3.6.2) Specifies the mailbox of the agent responsible for the actual transmission of the message. Defined as standard by RFC 822.
Mailbox for replies to message Mail standard IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2822 (section 3.6.2) When the "Reply-To:" field is present, it indicates the mailbox(es) to which the author of the message suggests that replies be sent. Defined as standard by RFC 822.
Primary recipient mailbox Mail standard IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2822 (section 3.6.3) Contains the address(es) of the primary recipient(s) of the message. Defined as standard by RFC 822.
Carbon-copy recipient mailbox Mail standard IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2822 (section 3.6.3) Contains the addresses of others who are to receive the message, though the content of the message may not be directed at them. Defined as standard by RFC 822.
Blind-carbon-copy recipient mailbox Mail standard IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2822 (section 3.6.3) Contains addresses of recipients of the message whose addresses are not to be revealed to other recipients of the message. Defined as standard by RFC 822.
Message identifier Mail standard IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2822 (section 3.6.4) Contains a single unique message identifier that refers to a particular version of a particular message. If the message is resent without changes, the original Message-ID is retained. Defined as standard by RFC 822.
Identify replied-to message(s) Mail standard IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2822 (section 3.6.4) The message identifier(s) of the original message(s) to which the current message is a reply. Defined as standard by RFC 822.
Related message identifier(s) Mail standard IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2822 (section 3.6.4) The message identifier(s) of other message(s) to which the current message may be related. In RFC2822, the definition was changed to say that this header field contains a list of all Message-IDs of messages in the preceding reply chain. Defined as standard by RFC 822.
Topic of message Mail standard IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2822 (section 3.6.5) Contains a short string identifying the topic of the message. Defined as standard by RFC 822.
Additional comments about the message Mail standard IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2822 (section 3.6.5) Contains any additional comments on the text of the body of the message. Warning: Some mailers will not show this field to recipients. Defined as standard by RFC 822.
Message key words and/or phrases Mail standards IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2822 (section 3.6.5) Contains a comma-separated list of important words and phrases that might be useful for the recipient. Defined as standard by RFC 822.
Date and time message is resent Mail standard IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2822 (section 3.6.6) Contains the date and time that a message is reintroduced into the message transfer system. Defined as standard by RFC 822.
Mailbox of person for whom message is resent Mail standard IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2822 (section 3.6.6) Contains the mailbox of the agent who has reintroduced the message into the message transfer system, or on whose behanlf the message has been resent. Defined as standard by RFC 822.
Mailbox of person who actually resends the message Mail standard IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2822 (section 3.6.6) Contains the mailbox of the agent who has reintroduced the message into the message transfer system, if this is different from the Resent-From value. Defined as standard by RFC 822.
Mailbox to which message is resent Mail standards IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2822 (section 3.6.6) Contains the mailbox(es) to which the message has been resent. Defined as standard by RFC 822.
Mailbox(es) to which message is cc'ed on resend Mail standard IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2822 (section 3.6.6) Containes the mailbox(es) to which message is cc'ed on resend. Defined as standard by RFC 822.
Mailbox(es) to which message is bcc'ed on resend Mail standard IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2822 (section 3.6.6) Containes the mailbox(es) to which message is bcc'ed on resend. Defined as standard by RFC 822.
Resent reply-to Mail obsolete IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2822 Resent Reply-to. Defined by RFC 822, obsoleteed by RFC2822.
Message identifier for resent message Mail standard IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2822 (section 3.6.6) Contains a message identifier for a resent message. Defined as standard by RFC 822.
Message return path Mail standard IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2822 (section 3.6.7) Return path for message response diagnostics. See also, RFC 2821. Defined as standard by RFC 822.
Mail transfer trace information Mail standard IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2822 (section 3.6.7) Contains information about receipt of the current message by a mail transfer agent on the transfer path. See also, RFC 2821. Defined as standard by RFC 822.
Message encryption information Mail obsolete IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 822 Defined by RFC 822, but was found to be inadequately specified, not widely implemented, and removed in RFC 2822. Current practice is to use separate encryption, such as S/MIME or OpenPGP, possibly in conjunction with RFC 1847 MIME security multiparts.
Mailbox for sending disposition notification Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2298 Indicates that the sender wants a disposition notification when this message is received (read, processed, etc.) by its recipients.
Disposition notification options Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2298 For optional modifiers on disposition notification requests.
Language(s) for auto-responses Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 3282 Indicates a language that the message sender requests be used for responses. Accept-language was not designed for email, but has been considered to be useful as input to the generation of automatic replies. Some problems have been noted concerning its use with email, including but not limited to: determination of the email address to which it refers; cost and lack of effective internationalization of email responses; interpretation of language subtags; determining what character set encoding should be used.
Original message identifier Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 3297 Original message identifier used with resend of message with alternative content format, identifies the original message data to which it corresponds.
PICS rating label Mail standard W3C (mailto:web-human@w3.org) World Wide Web Consortium PICS-labels Ratings label to control selection (filtering) of messages according to the PICS protocol. Specified for general use with RFC822 message format, with HTTP-specific extensions
Message encoding and other information Mail experimental Albert K. Costanzo (mailto:AL@AKC.COM) AKC Consulting Inc. RFC 1505 Used in several different ways by different mail systems. Some use it for a kind of content-type information, some for encoding and length information, some for a kind of boundary information, some in other ways.
URL of mailing list archive Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2369 Contains URL to use to browse the archives of the mailing list from which this message was relayed.
URL for mailing list information Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2369 Contains URL to use to get a information about the mailing list from which this message was relayed.
Mailing list identifier Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2919 Stores an identification of the mailing list, through which this message was distributed.
URL for mailing list owner's mailbox Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2369 Contains URL to send e-mail to the owner of the mailing list from which this message was relayed.
URL for mailing list posting Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2369 Contains URL to use to send contributions to the mailing list from which this message was relayed.
URL for mailing list subscription Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2369 Contains URL to use to get a subscription to the mailing list from which this message was relayed.
URL for mailing list unsubscription Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2369 Contains URL to use to unsubscribe the mailing list from which this message was relayed.
Type or context of message Mail Standards track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC3458 Provides information about the context and presentation characteristics of a message. Can have the values 'voice-message', 'fax-message', 'pager-message', 'multimedia-message', 'text-message', 'none'.
Trace of distribution lists passed Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2156 Trace of distribution lists passed. (MIXER X.400 mapping, not for general use.)
Controls forwarding to alternate recipients Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2156 Controls whether this message may be forwarded to alternate recipients such as a postmaster if delivery is not possible to the intended recipient. Default: Allowed. RFC 2156 (MIXER), not for general use.
Body part types in message Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2156 Which body part types occur in this message. RFC 2156 (MIXER), not for general use.
Return content on non-delivery? Mail obsolete IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 1327 Indicates whether the content of a message is to be returned with non-delivery notifications. Introduced by RFC 1327, and subsequently changed by RFC 2156 to avoid confusion with MIME defined fields.
Request delivery report generation Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2156 Indicates whether a delivery report is wanted at successful delivery. Default is not to generate such a report. RFC 2156 (MIXER), not for general use.
Non-delivery report required? Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2156 Indicates whether non-delivery report is wanted on delivery error. Default is to generate such a report. RFC 2156 (MIXER), not for general use.
Reference message to be replaced Mail obsolete IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 1327 Reference to a previous message being corrected and replaced. Compare to 'Supersedes:' used in Usenet News. Introduced by RFC 1327, and subsequently renamed by RFC 2156 to 'Supersedes'.
Reference message to be replaced Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2156 Reference to a previous message being corrected and replaced. Renamed version of obsolete 'Obsoletes' header field. RFC 2156 (MIXER), not for general use.
Message content identifier Mail obsolete IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 1327 A text string which identifies the content of a message. Introduced by RFC 1327, and subsequently changed by RFC 2156 to avoid confusion with MIME defined fields. Gateways which reverse map may support the old field.
Message delivery time Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2156 The time when a message was delivered to its recipient. RFC 2156 (MIXER), not for general use.
Message expiry time Mail obsolete IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 1327 Time at which a message loses its validity. Introduced by RFC 1327, and subsequently changed by RFC 2156 to 'Expires:'.
Message expiry time Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2156 Time at which a message loses its validity. Renamed version of obsolete Expiry-Date header field. RFC 2156 (MIXER), not for general use.
Time by which a reply is requested Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2156 Latest time at which a reply is requested (not demanded). RFC 2156 (MIXER), not for general use.
Message importance Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2156 A hint from the originator to the recipients about how important a message is. Values: High, normal or low. Not used to control transmission speed. Proposed for use with RFC 2156 (MIXER) and RFC 2421 (VPIM).
Body parts are missing. Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2156 Body parts are missing. RFC 2156 (MIXER), not for general use.
Message priority Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2156 Can be 'normal', 'urgent' or 'non-urgent' and can influence transmission speed and delivery. RFC 2156 (MIXER), not for general use.
Message content sensitivity Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2156 How sensitive it is to disclose this message to other people than the specified recipients. Values: Personal, private, company confidential. The absence of this header field in messages gatewayed from X.400 indicates that the message is not sensitive. Proposed for use with RFC 2156 (MIXER) and RFC 2421 (VPIM).
X.400 message content lenguage Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2156 Can include a code for the natural language used in a message, e.g. 'en' for English. See also 'Content-Language'. RFC 2156 (MIXER), not for general use.
Conversion allowed? Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2156 The body of this message may not be converted from one character set to another. Values: Prohibited and allowed. RFC 2156 (MIXER), not for general use.
Lossy conversion allowed? Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2156 The body of this message may not be converted from one character set to another if information will be lost. Values: Prohibited and allowed. RFC 2156 (MIXER), not for general use.
Message type: delivery report? Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2156 Only used with the value 'Delivery Report' to indicates that this is a delivery report gatewayed from X.400. RFC 2156 (MIXER), not for general use.
Automatically submitted indicator Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2156 Has been automatically submitted. RFC 2156 (MIXER), not for general use.
Automatically forwarded indicator Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2156 Has been automatically forwarded. RFC 2156 (MIXER), not for general use.
X.400 IPM extensions discarded Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2156 Can be used in Internet mail to indicate X.400 IPM extensions which could not be mapped to Internet mail format. RFC 2156 (MIXER), not for general use.
X.400 MTS extensions discarded Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2156 Can be used in Internet mail to indicate X.400 MTS extensions which could not be mapped to Internet mail format. RFC 2156 (MIXER), not for general use.
Disclose names of other recipients? Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2156 Tells whether recipients are to be told the names of other recipients of the same message. This is primarily an X.400 facility. In X.400, this is an envelope attribute and refers to disclosure of the envelope recipient list. Disclosure of other recipients is in Internet mail done via the To:, cc: and bcc: header fields. Not for general use.
Deferred delivery information Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2156 Provides information about deferred delivery service to the recipient. RFC 2156 (MIXER), not for general use.
Latest delivery time requested Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2156 Provides the recipient information about requested delivery, but will not be acted on by the SMTP infrastrucuture. RFC 2156 (MIXER), not for general use.
Originator return address Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2156 Originator return address. RFC 2156 (MIXER), not for general use.
Message content identifier Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2156 A text string which identifies the content of a message. Renamed version of obsolete Content-Identifier field. RFC 2156 (MIXER), not for general use.
Return content on non-delivery? Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2156 Indicates whether the content of a message is to be returned with non-delivery notifications. Renamed version of obsolete Content-Return field. RFC 2156 (MIXER), not for general use.
X400 content type Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2156 X400 content type. RFC 2156 (MIXER), not for general use.
X400 MTS-Identifier Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2156 X400 MTS-Identifier. RFC 2156 (MIXER), not for general use.
X400 Originator Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2156 X400 Originator. RFC 2156 (MIXER), not for general use.
X400 Received Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2156 X400 Received. RFC 2156 (MIXER), not for general use.
X400 Recipients Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2156 X400 Recipients. RFC 2156 (MIXER), not for general use.
X400 Trace Mail standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2156 X400 Trace. RFC 2156 (MIXER), not for general use.
MIME version number MIME standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2045 (section 4) An indicator that this message is formatted according to the MIME standard, and an indication of which version of MIME is utilized.
Identify content body part MIME standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2045 (section 7) Specifies a Unique ID for one MIME body part of the content of a message.
Description of message body part MIME standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2045 (section 8) Description of a particular body part of a message, for example a caption for an image body part.
Content transfer encoding applied MIME standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2045 (section 6) Coding method used in a MIME message body part.
MIME content type MIME standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2045 (section 5) Format of content (character set etc.) Note that the values for this header field are defined in different ways in RFC 1049 and in MIME (RFC 2045), look for the 'MIME-version' header field to understand if Content-Type is to be interpreted according to RFC 1049 or according to MIME. The MIME definition should be used in generating mail. RFC 1049 has 'historic' status. RFC 1766 defines a parameter 'difference' to this header field. Various other Content-Type define various additional parameters. For example, the parameter 'charset' is mandatory for all textual Content-Types. See also: RFC 1049, RFC 1123: 5.2.13, RFC 1766: 4.1.
Base to be used for resolving relative URIs within this content part. MIME standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2110 Base to be used for resolving relative URIs within this content part. See also Content-Location. This header was included in the first version of MHTML and HTTP 1.1 but removed in the second version (RFC2557).
URI for retrieving a body part MIME standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2557 URI using which the content of this body-part part was retrieved, might be retrievable, or which otherwise gives a globally unique identification of the content.
Indicates content features of a MIME body part MIME standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2912 (section 3) The 'Content-features:' header can be used to annotate a MIME body part with a media feature expression, to indicate features of the body part content. See also: RFC 2533, RFC 2506, RFC 2045.
Intended content disposition and file name MIME standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2183 Whether a MIME body part is to be shown inline or is an attachment; can also indicate a suggested filename for use when saving an attachment to a file.
Language of message content MIME standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 3282 Can include a code for the natural language used in a message, e.g. 'en' for English. Can also contain a list of languages for a message containing more than one language.
Alternative content available MIME work-in-progress IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 3297 Information about the media features of alternative content formats available for the current message.
MD5 checksum of content MIME standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 1864 Checksum of content to ensure that it has not been modified.
Time duration of content MIME standards-track IETF (mailto:iesg@ietf.org) Internet Engineering Task Force RFC 2424 Time duration of body part content, in seconds (e.g. for audio message).
This specification provides initial registrations of mail and MIME header fields in the "Permanent Message Header Field Registry", defined by Registration procedures for message header fields.
No security considerations are introduced by this registration document beyond those already inherent in use of the mail message header fields referenced.
Most of the information in this document has been derived from Jacob Palme's work in RFC 2076 and subsequent updates . The authors also gratefully acknowledge contributions and constructive input from: Mark Nottingham, Bruce Lilly, Keith Moore and Charles Lindsey (the mention of whom is not intended to imply their unqualified support for material herein).
Registration procedures for message headers Nine by Nine
UK GK-IETF@ninebynine.org http://www.ninebynine.net/
BEA Systems
235 Montgomery St. Level 15 San Francisco CA 94104 USA mnot@pobox.com
Western Research Laboratory, Compaq Computer Corporation
250 University Avenue Palo Alto CA 94305 US 1 650 617 3304 (email preferred) JeffMogul@acm.org
PICS Label Distribution Label Syntax and Communication Protocols World Wide Web Consortium
jmiller@w3.org http://www.w3c.org
Spyglass
timk@spyglass.com
AT&T
presnick@research.att.com
OpenMarket
treese@OpenMarket.com
Common Internet Message Header Fields Stockholm University/KTH
[[[Please remove this section on final publication]]]
Change status of headers defined by RFC822 to standard, except Encrypted which is obsolete. Add RFC822 to references. Set ?RFC strict=yes, and clean up ID-nits.
Final editorial tidying. Acknowledge additional contributions. Minor editorial fixes. Fix up message-headers I-D reference.
Added Accept-Language header, with some warning text concerning its use with email. Removed Originator headere, since it is not used as a mail message header. Fix up report generator error in author/change controller handling. Using a new version of the RDF-to-documentation generator for registry entry data. Revised format of registry entries to avoid some duplication of document and author details. Added documents referenced by the regsitration entries to the references section, and added citations to the entries themselves. Added and revised header details, per comments from Bruce Lilly.
Incorporated small changes to specific header field descriptions, suggested by Jacob. Separated Mail and MIME header fields. Corrected specification reference for MIXER headers (RFC 2156). Changed applicable protocol for MIME header fields. Other smaller corrections. Removed provisional mail header registrations from this document. Added Jacob Palme as co-editor.
Minor editorial. Updated some contact information. Regenerated registry tables with revised software. Revised change controller information in line with registry specification. Cleaned up some table layout.
Added data for permanent and provisional registries. Revised form of registry entry content. (Auto-generated from RDF data.) Document initially created.
[[[Please remove this section on final publication]]] Resolve reference to registration procedure RFC . Remove any remaining [[[editorial comments]]].