Hi Timo,
Which v1.0? (Which one's Debian 4.0? :) I wish Debian used Ubuntu-style year+month numbers as versions. The only Debian versions I remember are stable, testing and unstable..)
:-) It's pretty old, dovecot --version returns 1.0.rc15
Anyway, I don't think there have been any actual STATUS command related bugs in Dovecot. If opening the mailbox shows that there are new mails, it's more likely that it's a Thunderbird bug/configuration issue.
It works fine when I enable this per-folder-query setting in Thunderbird, but especially on a mobile connection, this causes a lot of overhead and takes quite a while with my about 50 folders. :-)
and IMAP_ENHANCEDIDLE=1 in Courier?
This is done by default, if compiled with dnotify/inotify (dovecot --build-options shows). But it's not related to your problem anyway.
Seems I am lucky then: Build options: ioloop=poll notify=dnotify ipv6 openssl
;-) I will try with a recent Dovecot version and follow-up if things don't work. Thanks for the fast and great help!
Florian