[Mailman-Users] Bad From address

[Németh Balázs]

Hi,

I have set up Mailman on my Linux box. It has dynamic IP, so its
hostname (formatc.dnsalias.com) is provided by a Dynamic DNS provider.
Nearly everything works fine, it forwars e-mails, the web interface
works good, but if someone wants to join to a list, he got a message
from eg. formatc-l-owner at formatc.hu instead of
formatc-l-owner at formatc.dnsalias.com so when he replies to it (eg.
confirmation letter), mailman won't get it.
I would be happy, if someone can tell me, where to look for the
problame.

Thanks in advance:
 Németh Balázs
 mailman at formatc.hu