[Mailman-Developers] Exposing not advertised lists via nntp archiver

Hi,

I have a conceptional problem:

There are mailinglists with a pubic archive but that not be advertised by the server. The nntp archiver now have to supply a list of all available archives. If this list does not contain a mailing list, in most news clients you do not have a chance to subscribe to that group and read the posts.

How to solve that? The only possibility I could think of uses the filter mechanism of the available newsgroups. The clients could supply a regexp like filter. I would implement a mechanism, that shows unadvertized lists with an archive only if the supplied filter is equal to the newsgroup name. Any other idea?

Alex