If telnet into Dovecot on my server, it doesn't explicitly indicate SORT and THREAD capabilities:
You did not issue the "1 capability"-command. If you do so, you will get this (or similar):
r...@terra:~# telnet localhost 143 Trying 127.0.0.1... Connected to localhost. Escape character is '^]'. * OK [CAPABILITY IMAP4rev1 LITERAL+ SASL-IR LOGIN-REFERRALS ID ENABLE STARTTLS AUTH=PLAIN AUTH=LOGIN] Dovecot ready. 1 capability * CAPABILITY IMAP4rev1 LITERAL+ SASL-IR LOGIN-REFERRALS ID ENABLE SORT SORT=DISPLAY THREAD=REFERENCES THREAD=REFS MULTIAPPEND UNSELECT IDLE CHILDREN NAMESPACE UIDPLUS LIST-EXTENDED I18NLEVEL=1 CONDSTORE QRESYNC ESEARCH ESORT SEARCHRES WITHIN CONTEXT=SEARCH LIST-STATUS QUOTA STARTTLS AUTH=PLAIN AUTH=LOGIN 1 OK Capability completed.
which clearly states "SORT" and "THREAD". best regards, Anton
