distribution lists - service unavailable. Command output: Delivery to some recipients failed, code 550

[Liutauras Adomaitis]

Hello all,

i'm having problem with distribution lists implementation on Kolab:

sending mail to any DL configured with Kolab web interface fails. Sender gets 
one message back with error saying "email at domain.com: service unavailable. 
Command output: Delivery to some recipients failed, code 550" for all the 
emails in DL. I have googled a lot about this. But nothing works.
The main thread 
http://www.kolab.org/pipermail/kolab-devel/2006-January/004864.html discusses 
pretty much the same problem. But the solutions doesn't work for me.

From the logs I can see, that postfix smtpd process handles the DL ok, it 
queries ldap for DL emails and gets all the members of DL. Then it tries to 
submit to cyrus lmtpd - and lmpd answers - user does not exists.

Jun 28 11:48:34 penktas postfix/qmgr[24886]: 9A6329AC01: removed
Jun 28 11:48:34 penktas cyrus-master[5668]: about to  
exec /usr/lib/cyrus-imapd/lmtpd
Jun 28 11:48:34 penktas lmtp[5668]: executed
Jun 28 11:48:34 penktas lmtp[5668]: accepted connection
Jun 28 11:48:34 penktas lmtp[5668]: connection from penktas.domain.com 
[127.0.0.1] preauth'd as postman
Jun 28 11:48:34 penktas lmtp[5668]: verify_user(domain.com!user.allstaff) 
failed: Mailbox does not exist

I haven't found any info about how /etc/imapd.group file is used, but this 
file contains group allstaff
llstaff at infosaitas.lt:*:60006:user@ .....
Ldap also has cn=allstaff.

It seems to me, that either postfix is calling lmtpd with wrong user name (it 
should use DL members instead of DL email allstaff) or lmtpd doesn't know how 
to handle group/DL username. 

I'm not an expert in postfix or cyrus, so any help and hints were to dig would 
be nice.

thanks in advance

Liutauras