On Wed, 2010-08-18 at 14:49 +0200, Michael Kliewe wrote: > Currently I want to sort mails server-side by displayname of FROM and > TO. There is an extension for it, but I think dovecot does not support > it at the moment.
It is supported (note the SORT=DISPLAY capability). You'll just need to make the IMAP client use it.
