RFC 5335: Internationalized Email Headers
This RFC has been replaced. Do not implement against it for new work — it was formally obsoleted by RFC 6532.
Current version: RFC 6532 — Internationalized Email Headers
In plain English — editorial summary, not part of the RFC
Full internationalization of electronic mail requires not only the capabilities to transmit non-ASCII content, to encode selected information in specific header fields, and to use non-ASCII characters in envelope addresses. It also requires being able to express those addresses and the information based on them in mail header fields. This document specifies an experimental variant of Internet mail that permits the use of Unicode encoded in UTF-8, rather than ASCII, as the base form for Internet email header field. This form is permitted in transmission only if authorized by an SMTP extension, as specified in an associated specification. This specification Updates section 6.4 of RFC 2045 to conform with the requirements. This memo defines an Experimental Protocol for the Internet community.
Document record
- Document ID
- RFC5335
- Published
- September 2008
- Authors
- A. Yang
- Status
- EXPERIMENTAL
- Stream
- IETF
- Area
- app
- Pages
- 14
- Also known as
- —
- Obsoleted by:
- RFC 6532
Topics
Referenced by
One later RFC formally updates or obsoletes part of this document.
Related documents
Ranked automatically by shared keywords, IETF area and stream — not by editorial selection.
- RFC 6409Message Submission for MailUpdated
November 2011
- RFC 5137ASCII Escaping of Unicode CharactersCurrent
February 2008
- RFC 9839Unicode Character Repertoire SubsetsCurrent
August 2025
- RFC 5892The Unicode Code Points and Internationalized Domain Names for Applications (IDNA)Updated
August 2010
- RFC 6055IAB Thoughts on Encodings for Internationalized Domain NamesCurrent
February 2011
- RFC 4042UTF-9 and UTF-18 Efficient Transformation Formats of UnicodeCurrent
April 2005
- RFC 5198Unicode Format for Network InterchangeCurrent
March 2008
- RFC 4396RTP Payload Format for 3rd Generation Partnership Project (3GPP) Timed TextCurrent
February 2006
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The document record above — title, authors, date, status, stream, area, relationships, DOI and errata — is imported verbatim from the public RFC Editor index. The “in plain English” section is editorial: written by The metasystema editorial team, not part of the RFC. Where the two differ, the RFC text governs.
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