[Mailman-Users] host not found Error

[tomcat at downtownhost.com]

Hi
I recently renumbered the IPs on one of my servers, after that I
noticied that people could't subscribe to the mailing list that used
to works fine.
Checking at the mailman error logs I found this.

admin(13854): [----- Mailman Version: 2.0.11 -----]
admin(13854): [----- Traceback ------]
admin(13854): Traceback (innermost last):
admin(13854):   File "/usr/local/cpanel/3rdparty/mailman/scripts/driver", line 96, in run_main
admin(13854):     main()
admin(13854):   File "/usr/local/cpanel/3rdparty/mailman/Mailman/Cgi/subscribe.py", line 76, in main
admin(13854):     process_form(mlist, doc)
admin(13854):   File "/usr/local/cpanel/3rdparty/mailman/Mailman/Cgi/subscribe.py", line 187, in process_form
admin(13854):     mlist.AddMember(email, pw, digest, remote)
admin(13854):   File "/usr/local/cpanel/3rdparty/mailman/Mailman/MailList.py", line 1005, in AddMember
admin(13854):     text)
admin(13854):   File "/usr/local/cpanel/3rdparty/mailman/Mailman/Message.py", line 211, in __init__
admin(13854):     OutgoingMessage.__init__(self, text)
admin(13854):   File "/usr/local/cpanel/3rdparty/mailman/Mailman/Message.py", line 205, in __init__
admin(13854):     self['Message-ID'] = Utils.make_msgid(idstring='Mailman')
admin(13854):   File "/usr/local/cpanel/3rdparty/mailman/Mailman/Utils.py", line 769, in make_msgid
admin(13854):     idhost = socket.gethostbyaddr(socket.gethostname())[0]
admin(13854): error: host not found


To be honest, I'm lost, and I don't know how to solve it, can anybody
help me here?

Thanks in advance

-- 
Best regards,