[Mailman-Users] Allowing posting to list "A" by members of list "B"?

[Beau James]

We sometimes have related but distinct mailing lists, e.g. one
for coaches and one for referees in the same league.  Both lists
are moderated.

We'd like to turn on the flag to allow postings (still moderated)
only by members of the list.  For the usual reason: SPAMmers
are overwhelming the volunteer list moderators.

At the same time, we'd like to allow member of the related list
still to be able to post (postings still to be moderated).  That
is, we'd like the members of list "A" to be allowed to post to
list "B", without registering as members of list "B".

We could do this by, in effect, maintaining two copies of each
mailing list: one is the actual mailing list "A", and the other
is in the 'allowed posters' section of the list "B".  (And
vice-versa).

This is rather painful to administer, of course.

(Assuming both the mailing list memberships and the allowed
posters lists are stored in files, one could create a script
and cron job to periodically sync/merge the membership of list
"A" into the "allowed posters" of list "B".  Unfortunately, we
do not have that kind of shell access to the our list server.)

Any hints on how one might best accomplish this?

Thanks.

Beau