[Dovecot] Dovecot 1.0beta4 and Disconnected Problem

[Gerhard Wiesinger]

Hello!

Yesterday I upgraded from 1.0beta3 to 1.0beta4. I've major problems now 
with my inbox (quite large, 900MB) and another large folder. Thunderbird 
1.5 connects and disconnects. I tried to delete the indexes of dovecot and 
thunderbird without any sucess.

Finally I downgraded to 1.0beta3 and it works well again (Beta3 was 
running for a timeframe from when it came out and now without any 
problems).

Config is the same as for 1.0beta3.

Apr  3 07:30:27 bbs dovecot: imap-login: Login: user=<user1>,method=plain, rip=192.168.0.5, lip=192.168.0.2, TLS
Apr  3 07:30:27 bbs dovecot: imap(gerhard): Disconnected
Apr  3 07:30:27 bbs dovecot: imap-login: Login: user=<user1>, method=plain, rip=192.168.0.5, lip=192.168.0.2, TLS
Apr  3 07:30:28 bbs dovecot: imap(gerhard): Disconnected
Apr  3 07:30:28 bbs dovecot: imap-login: Login: user<user1>, method=plain, rip=192.168.0.5, lip=192.168.0.2, TLS
Apr  3 07:30:28 bbs dovecot: imap(gerhard): Disconnected

Any ideas how the problem can be found?

Thank you for the answer.

Ciao,
Gerhard