[Mailman-Users] mailman cannot send messages

[Geo]

Thanks for help...
FreeBSD 6.2, after installed mailman from port /usr/ports/mail/mailman
Apache is OK...but sendmail cannot work with mailman...I created list (named
"mailman"), but mailman replies for attempt to send message by the way:
----------------------------------------- 
The original message was received at Mon, 30 Jul 2007 02:00:40 +0400 (MSD)
from localhost [127.0.0.1]

   ----- The following addresses had permanent fatal errors -----
"|/usr/local/mailman/mail/mailman post mailman"
    (reason: 2)
    (expanded from: <mailman at bind9.cit.ru>)

   ----- Transcript of session follows -----
Group mismatch error.  Mailman expected the mail
wrapper script to be executed as group "mailman", but
the system's mail server executed the mail script as
group "mailnull".  Try tweaking the mail server to run the
script as group "mailman", or re-run configure,
providing the command line option `--with-mail-gid=mailnull'.
554 5.3.0 unknown mailer error 2
------------------------------------- 
>From post-installation instructions we can see:
"you have to choose SENDMAIL option on config build and port will set
MAIL_GID=mailnull to you",
but makefile in port containes :".if defined(WITH_SENDMAIL)...
MAIL_GID?     mailnull
.endif"
May be it's not enough