Other than 2.0, it refuses to talk to my server - does not even make a login attempt, but states "LOGIN failed" and asks for another password after a very minimal session:

T 10.0.0.132:1270 -> 10.0.0.8:143 [AP]
1 CAPABILITY..
##
T 10.0.0.8:143 -> 10.0.0.132:1270 [AP]
* CAPABILITY IMAP4 IMAP4rev1 ACL QUOTA LITERAL+ MAILBOX-REFERRALS NAMESPACE UIDPLUS ID NO_ATOMIC_RENAME UNSELECT CHILDREN MULTIAPPEND BINARY SORT THREAD=ORDEREDSUBJECT THREAD=REFERENCES ANNOTATEMORE IDLE
STARTTLS AUTH=CRAM-MD5 AUTH=DIGEST-MD5 SASL-IR LISTEXT LIST-SUBSCRIBED X-NETSCAPE..1 OK Completed..

The claws log claims it tries to authenticate with CRAM-MD5 and fails immediately, but the server does not even get that attempt. Secure auth broken?

Sevo