On two seperate mailing lists, run on two seperate sites, I'm having the
same problem with two seperate subscribers' sites.

Basically they're reinjecting previously sent messages to the mailing
lists.  That is, a message previously sent by, say, [log in to unmask] is
reappearing with a return address of [log in to unmask] and other header
information intact.  However, the Received: lines indicate that the
messages are originating from a different machine altogether (and it's
always the same machine for the same mailing list).

The problem seems to have gone away for one of the mailing lists, and the
other mailing list is moderated, so from a subscriber perspective things
are under control.  But from a listowner perspective it's bugging me to
keep getting the same messages submitted for approval over and over.  And
it's presumably increasing the load on the LISTSERV machine (though not by
much, since the messages aren't coming too close together).

I've mailed the administrators at the various sites.  Is there anything
else I can do?

Thanks,
jwgh