a weird problem with expire..

From: Michael Jones (mtj@iglou.compost.com)
Date: Tue, 10 Jun 1997 16:56:24 -0400

Because I run expire -o automatically every morning, and don't
want my mailing lists to expire without me explicitly saying so,
I use expire -r to get rid of read mailing list articles. So I
use expire -r @lists, where the file "lists" contains the name
of all my mailing lists. It seems, however, that it also likes
to expire articles out of comp.security.pgp.discuss. I can't
think of a reason for this, other than I also subscribe to the
pgp-users mailing list (even though I haven't been using pgp ;)).
Even forwarded articles to both c.s.p.d and pgp-users wouldn't be
stored only once, because I download my mailbox straight from my
shell account without going through uqwk. And, there are times
when it will expire everything out of the pseudo-newsgroup, but
nothing out of c.s.p.d.

Any ideas as to why this is happening?

-- 
Michael Jones, an irritating speck of dirt on the planet Earth, also a
 student of Computer Science and Philosophy at Western Kentucky University.
 I am not compost. Really. Trust me. Remember this in your replies to me.