[Dovecot] What does mailman do with a 'post' command?

[Masaharu Kawada]

Dear list,

I am sorry if this question should not be posted here, but I believe that
there are many experts of postfix or any other thing such as mailing lists
in this list. I am kind of in hurry and need some advices to know about
my questions. Could anyone in this list please answer my questions if you
know.

My questions are about routing work of mailman. As I am not quite
fimiliar with the use of mailman, I am sorry if this is a stupid question.

One of my customer gets the following log message into /var/log/maillog
at around 12:00 every day.

---</var/log/maillog>---
12:00:04 relay postfix/pickup[6279]: 244811C805C: uid=41 from=<mailman>
12:00:04 relay postfix/cleanup[21529]: 244811C805C:
message-id=<20100215030004.244811C805C at example.co.jp>
12:00:04 relay postfix/qmgr[20068]: 244811C805C:
from=<mailman at example.co.jp>, size=1728, nrcpt=1 (queue active)
12:00:04 relay postfix/local[21232]: 244811C805C:
to=<mailman at example.co.jp>, orig_to=<mailman>, relay=local, delay=0.17,
delays=0.05/0/0/0.12, dsn=2.0.0, status=sent (delivered to command:
/usr/lib/mailman/mail/mailman post mailman)
----

This message seems that it delivers a command
'/usr/lib/mailman/mail/mailman post'
to execute against the mailman mailing list, however, the customer never
use mailman mailing list on their system. One thing that I doubt is that 
a cronjob in /etc/cron.d/mailman does something relevant of this because
the post time of the messages is always reight after the following work.

---</etc/cron.d/mailman>---
0 12 * * * mailman /usr/lib/mailman/cron/senddigests

or

0,5,10,15,20,25,30,35,40,45,50,55 * * * * mailman
/usr/lib/mailman/cron/gate_news
---

I'm afraid that I don't have /etc/mailman/aliases file of cutomer's, 
but by default(in my test env), it should looks like below.

</etc/mailman/aliease>
# STANZA START: mailman
# CREATED: Mon Jan 25 16:48:18 2010
mailman: "|/usr/lib/mailman/mail/mailman post mailman"
mailman-admin: "|/usr/lib/mailman/mail/mailman admin mailman"
mailman-bounces: "|/usr/lib/mailman/mail/mailman bounces mailman"
mailman-confirm: "|/usr/lib/mailman/mail/mailman confirm mailman"
mailman-join: "|/usr/lib/mailman/mail/mailman join mailman"
mailman-leave: "|/usr/lib/mailman/mail/mailman leave mailman"
mailman-owner: "|/usr/lib/mailman/mail/mailman owner mailman"
mailman-request: "|/usr/lib/mailman/mail/mailman request mailman"
mailman-subscribe: "|/usr/lib/mailman/mail/mailman subscribe mailman"
mailman-unsubscribe: "|/usr/lib/mailman/mail/mailman unsubscribe mailman"
# STANZA END: mailman

My questions are as follows.

1.What exactly is the cause the message in /var/log/maillog?
2.Why does the messages send to mailman(mailman at example.co.jp) user
even though that mailing list never be used?

OS:RHEL5
postfix-2.3.3-2.1.el5_2
mailman-2.1.9-4.el5

Any comments would be greatly appreciated.

Best Regards,

-- 
-------------------
Masaharu Kawada
Associate Technical Support Engineer
Red Hat K K
Ebisu Neonato 5F
1-18 Ebisu 4-chome, Shibuya-ku
Tokyo 150-0013, Japan
Direct: +81-3-5798-8482