Revision 06 of the Crispin/Newman IMAP URLAUTH Extension draft is available from the on-line Internet-Drafts directories.
Changes from revision 05: Minor clarifications in the language. Removal of “compose” role from list of specified AUTHROLE= values. AUTHROLE=submit now accepts optional user ID argument. URLFETCH now takes exactly one URL, and returns exactly one untagged response. Addition of SIGNURL command and response to the grammar.
Abstract: ‘This document describes the URLAUTH extension to the Internet Message Access Protocol (IMAP) (RFC 3501) and the IMAP URL Scheme (IMAPURL) (RFC 2192). This extension provides a means by which an IMAP client can create “signed” URLs carrying authorization to access limited message data on the IMAP server.’
http://www.ietf.org/internet-drafts/draft-crispin-imap-urlauth-06.txt