expire/search machine

[Jean-Michel BESNARD]

Hello,

I have to manage a newsserver with different newsgroups. This groups are
readable with a webapplication (Nwesservlet) and I have any things to
solve :

I want to use expire but not with a date of expiration but with a limit
of news on the group ( for example 100 News, if there is already 100News
and I send one the more is expired)

I also want to make search machine for the news but I don´t know if
there are already solutions/program and I think  if a news is expired,
this news is no more availible (delete) and that make a little problem.

Jean-Michel