[Mailman-Users] newbie: Who is mailman at domain.com

[onesir mail]

Hi,

My apologies in advance if this proves to be a silly question - please 
point me to the silly answer.

I have used cPanel X to set up a couple of one-way announcement 
mailing lists using mailman.  I have no problems with the general 
operation of mailman.

The mailman generated domain mailing lists page contains the following 
line:- 

If you are having trouble using the lists, please contact 
mailman at domain.com. (where domain is my own domain)

I have sent mail to this address but it seems to be lost in a black 
hole.  By default all unknown address e-mails sent to my domain end up 
in the webmaster inbox.

Does anyone know where mail sent to mailman at domain.com is routed?

Regards,