expiring news by raising low water mark ...

[Katsuhiro Kondou]

In article <Pine.BSF.4.21.0001170907420.46499-100000 at thelab.hub.org>,
	The Hermit Hacker <scrappy at hub.org> wrote;

} I realize that this may be an odd request, but at the university I work
} at, the profs use the news server for 'course discussions' and want to
} periodically purge news pre-date X ... I'm figuring that the easiest way
} to do that would be to mark all articles in a group less then 'article #Y'
} as expired ...
:
} Is there any way I can do this? 

How about '-p' option for expire or expireover?
-- 
Katsuthiro Kondou