Well, I've got a monday, the sources for mailman-2.1.1 on atomicrocketturtle.com.
The firts problem, it's whit rpmbuild -bb mailman*.spec, becuase problem with create dir with users and groups.
I tried compiling mailman form other source and installing. (This create dirs and user and groups.)
After, compiling mailman-psa-2.1.1
Dont' work.
Go to forum on atomicrocketturtle.com.
See the permission for /var/mailman
Change to popuser.popuser
Same error...
Go this link:
Error
Thanks for you time.
NOTE: Redhat 7.3, plesk 5.0.5