imuxsock begins to drop messages

[mailingliste at dreampixel.de]

Hi at all,

in /var/log/messages I found this messages:

Dec 16 05:34:35 kolab rsyslogd-2177: imuxsock lost 34 messages from  
pid 6491 due to rate-limiting
Dec 16 06:47:03 kolab rsyslogd-2177: imuxsock begins to drop messages  
from pid 6492 due to rate-limiting
Dec 16 06:47:11 kolab rsyslogd-2177: imuxsock lost 102 messages from  
pid 6492 due to rate-limiting
Dec 16 07:02:11 kolab rsyslogd-2177: imuxsock begins to drop messages  
from pid 6491 due to rate-limiting
Dec 16 07:02:12 kolab rsyslogd-2177: imuxsock begins to drop messages  
from pid 6492 due to rate-limiting
Dec 16 09:46:51 kolab rsyslogd-2177: imuxsock begins to drop messages  
from pid 6963 due to rate-limiting
Dec 16 09:46:54 kolab rsyslogd-2177: imuxsock lost 143 messages from  
pid 6963 due to rate-limiting
Dec 16 09:46:58 kolab rsyslogd-2177: imuxsock begins to drop messages  
from pid 6963 due to rate-limiting
Dec 16 09:47:00 kolab rsyslogd-2177: imuxsock lost 49 messages from  
pid 6963 due to rate-limiting
Dec 16 09:47:04 kolab rsyslogd-2177: imuxsock begins to drop messages  
from pid 6963 due to rate-limiting

I've checked the pid. these belong to:

6491 ?        S      0:01 amavisd (ch3-avail)
6492 ?        S      0:03 amavisd (ch4-avail)

to 6963, there is no process.

could there be a context with my other problem that the kolab-server  
fetches the mailing lists from my second mail domain  
(mailingliste at dreampixel.de, primary domain ist gehr-edv.de) but these  
mails arrive nowhere?

here is perhaps a full queue?

how can I check this?

with best regards
sven