Data format error: : Mailbox doesn't exist

[Sebastian Haas]

Hello list,

I have a very strange problem using Postfix and Cyrus together. If I 
send an mail with more then one local recipient, Cyrus fails to deliver 
the mail, only the first recipient will get the mail. Postfix generates 
a bounce message.

This is the returned message (looks similar to the logs):

<test1 at local-dom.net>: data format error. Command output: : Mailbox does 
not exist

<test2 at local-dom.net>: data format error. Command output: : Mailbox does 
not exist

Log output:
Nov  9 08:01:44 mailserver postfix/pipe[10522]: D1EA8BCCE: 
to=<test1 at local-dom.net>, relay=cyrus, delay=1, status=bounced (data 
format error. Command output: : Mailbox does not exist )
Nov  9 08:01:44 mailserver postfix/pipe[10522]: D1EA8BCCE: 
to=<test2 at local-dom.net>, relay=cyrus, delay=1, status=bounced (data 
format error. Command output: : Mailbox does not exist )

If I send the mail itemized it is delivered right to each recipient.

Postfix delivers message to Cyrus via a Unix type socket to lmtpd.

My Cyrus version: v2.1.18-IPv6-Debian-2.1.18-1
The box runs on Linux Kernel 2.6.4

What could be the problem? Did you need any additional information?

-- 
Mit freundlichen Gruessen/Best Regards,
Sebastian Haas