Filter mailing lists to a local "newsgroups"

Hi,

I'm fairly certain I've seen this issue addressed before, but I
can't find my pointers to the answer.  I subscribe to over 20
fairly active mailing lists.  I use procmail to divide these
messages into different "inboxes".  What I'd like to do instead
is have procmail send the mail to a program "x" which will process
it and turn it into a local newsgroup...ie  local.procmail
local.inet-access, local.redhat, etc.

I am running on a linux box, using RedHat 4.2, running kernel 2.0.30,
I have tin setup, but I don't have any sort of externel newsfeed
whatsoever (not that this should matter).  

I know this can be done--please slap me on the head and tell me
where I've seen this info before.  Or if you do this yourself,
please tell me how you do it.

Thanks,
mark

Mark R. Cervarich
Shelfspace.com