[Kolab3] Postfix: lmtp-socket not found by postfix

[Henning Holly]

Hi,

subject says everything. I get mails outbound correctly via relayhost by
postfix, but no mail can be received, from neither internal nor external
addresses.

postfix/lmtp[24112]: A9E9440209: to=<hh at hollermann.eu>,
orig_to=<henning at hollermann.net>, relay=none, delay=0.34,
delays=0.27/0.07/0/0, dsn=4.4.1, status=deferred (connect to
eolize.localdomain[/var/lib/imap/socket/lmtp,lmtp:unix:/var/lib/imap/socket/lmtp]:
No such file or directory)

I read here
https://discussions.apple.com/thread/2222982?start=0&tstart=0, but
nothing worked. Permissions granted on that socket file for cyrus and
postfix users (both in group mail).

Socket is recreated, when deleted after postfix/cyrus shutdown.

What can I do?

Henning