[Mailman-Users] GID Error..

[Sadananda B Rai]

Hello All,
         I have configured mailman and I am running postfix. I am getting a
problem in adding aliases and once I send replay to mailman created lists I
get error as fallow....
Sep 23 17:15:51 mail Mailman mail-wrapper: Failure to exec script. WANTED
gid 12, GOT gid 99.  (Reconfigure to take 99?)
I hope somebody can help me to solve this problem as the earliest. Thanks in
advance.....
Sadananda Rai