As described at the URL, there's no option to specify PREAUTH authentication for IMAP (or at least I couldn't find it), which in particular makes it impossible for to use kmail with SSH public key authentication (where the IMAP session is authenticated and opened in advance). Reproducible: Always Steps to Reproduce: 1. Say dovecot.server.org is your IMAP server that supports SSH public key authentication. 2. 'ssh dovecot.server.org "exec /usr/lib/dovecot/imap"' opens an IMAP session on that server. 3. There's no option for kmail to do 2 and use that session going forward. Actual Results: As described in "Steps to Reproduce". Expected Results: kmail should be able to use SSH for key-based authentication and session setup.
See also the 'server command' option in Evolution, and similar options in alpine, mutt, anything that uses libetpan, etc. Where sysadmins prefer to give *only* SSH public key access to servers, and users prefer to use ssh-agent, access to IMAP over SSH is extremely useful.
The IMAP resource has a new maintainer, reassigning to him.
*** This bug has been marked as a duplicate of bug 49871 ***