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IMAP Support for UTF-8
RFC 6855

Approval announcement
Draft of message to be sent after approval:


From: The IESG <>
To: IETF-Announce <>
Cc: RFC Editor <>,
    eai mailing list <>,
    eai chair <>
Subject: Protocol Action: 'IMAP Support for UTF-8' to Proposed Standard (draft-ietf-eai-5738bis-12.txt)

The IESG has approved the following document:
- 'IMAP Support for UTF-8'
  (draft-ietf-eai-5738bis-12.txt) as Proposed Standard

This document is the product of the Email Address Internationalization
Working Group.

The IESG contact persons are Barry Leiba and Pete Resnick.

A URL of this Internet Draft is:

Ballot Text

[Please note: This document is one a set of four interdependent


These documents should be reviewed, evaluated, and understood

Technical Summary

      These four EAI documents make up a set that are interdependent
      and should be reviewed, evaluated, and understood together.  Their
      abstracts have been examined and verified to sufficiency to
      describe the individual documents.

      The abstract for this particular document reads:

         This specification extends the Internet Message Access Protocol
         version 4rev1 (IMAP4rev1) to support UTF-8 encoded
         international characters in user names, mail addresses and
         message headers.  This specification replaces RFC 5738.

Working Group Summary

      No particular process issues of note. The WG had extensive and
      constructive discussions about the role of "downgrading" (e.g.,
      converting a message stored on the server that contains non-ASCII
      header or envelope information) in the transition to an all-i18n
      environment.  Some of those issues and tradeoffs are discussed in
      draft-ietf-eai-popimap-downgrade and
      draft-ietf-eai-simpledowngrade.  In some cases, the best strategy
      may be to "hide" those messages that cannot be delivered without
      change to legacy clients either with or without some attempt at an
      error message.  A complete treatment of those options is
      impossible because the optimal strategies will depend considerably
      on local circumstances.  Consequently the base IMAP and POP3
      documents are no longer dependent on particular downgrading
      choices and that two methods presented are, to a considerable
      extent, just examples.  They are recommended as alternative
      Standards Track documents because they are protocol specifications
      and their sometimes-subtle details have have been carefully worked
      out, even though the WG has no general recommendation to make
      between them (or other strategies).

      While opinions differ in the WG about which downgrading mechanisms
      are likely to see the most use, if any, consensus is strong that
      these four documents represent the correct output.

Document Quality

      Some development and interoperability testing has occurred and is
      progressing.  There are strong commitments in various countries to
      implement and deploy the EAI (more properly, SMTPUTF8) messages
      and functions specified in RFCs 6530 through 6533.  Those messages
      will be inaccessible to many users without POP3 and IMAP support,
      so these specifications are quite likely to be implemented and
      deployed in a timely fashion.

      Reviewers who made particular contributions prior to IETF Last
      Call are acknowledged in the documents.  See Section 3 for
      additional information.


      Document Shepherd:   John C Klensin
      Responsible Area Director:   Pete Resnick

         Note that Pete Resnick is listed as a co-author on this
         document as a result of contributions well before he became AD
         (and primarily to its the Experimental predecessor.  He has not
         been actively involved in an author or editor role since
         joining the IESG.

RFC Editor Notes (late addition; sorry, IESG Secretary)

The document contains the pre-5378 disclaimer, but that isn't necessary; please
remove it.

Also, please add an informative reference to RFC 5530, and add a citation to it in
Section 6:
   A server that
   advertises "UTF8=ONLY" will reject with a "NO [CANNOT]" response any
   command that might require UTF-8 support and is not preceded by an
   "ENABLE UTF8=ACCEPT" command.
   A server that
   advertises "UTF8=ONLY" will reject with a "NO [CANNOT]" response [RFC5530]
   any command that might require UTF-8 support and is not preceded by an
   "ENABLE UTF8=ACCEPT" command.

RFC Editor Note