Mailman 2.1 and MAILMAN_GROUP problem

After upgrading a system to OpenBSD 4.6 and Mailman 2.1.12, Mailman refused to start, giving the error:-

# /usr/local/lib/mailman/bin/mailmanctl -s -q start
Traceback (most recent call last):
File "/usr/local/lib/mailman/bin/mailmanctl", line 548, in
main()
File "/usr/local/lib/mailman/bin/mailmanctl", line 341, in main
check_privs()
File "/usr/local/lib/mailman/bin/mailmanctl", line 288, in check_privs
gid = grp.getgrnam(mm_cfg.MAILMAN_GROUP)[2]
KeyError: 'getgrnam(): name not found: '

I fixed this by adding:-

MAILMAN_GROUP = '_mailman'

to the mm_cfg.py file. Of course your group name may be different.