mail-to-news is a program for forwarding the incoming emails to a group hosted on a NNTP server.
I tested mail-to-news on GNU/Linux, but it should work without many problems on similar systems, it needs an UNIX-like environment. Anyway I didn't test it a lot, please consider it a beta version. If you give it a try, your feedback would be appreciated.
You can read the mail-to-news manual online: <info/index.html>.
You can download mail-to-news from <http://download.savannah.gnu.org/releases/mail-to-news>.
The development area is located at: <http://savannah.nongnu.org/projects/mail-to-news>.