Network Working Group M. Crispin
Request for Comments: 1732 University of Washington
Category: Informational December 1994
IMAP4 COMPATIBILITY WITH IMAP2 AND IMAP2BIS
Status of this Memo
This memo provides information for the Internet community. This memo
does not specify an Internet standard of any kind. Distribution of
this memo is unlimited.
Introduction
This is a summary of hints and recommendations to enable an IMAP4
implementation to interoperate with implementations that conform to
earlier specifications. None of these hints and recommendations are
required by the IMAP4 specification; implementors must decide for
themselves whether they want their implementation to fail if it
encounters old software.
IMAP4 has been designed to be upwards compatible with earlier
specifications. For the most part, IMAP4 facilities that were not in
earlier specifications should be invisible to clients unless the
client asks for the facility.
In some cases, older servers may support some of the capabilities
listed as being "new in IMAP4" as experimental extensions to the
IMAP2 protocol described in RFC 1176.
This information may not be complete; it reflects current knowledge
of server and client implementations as well as "folklore" acquired
in the evolution of the protocol.
Crispin