The news setup around {ai,theory,na}.toronto.edu looks
roughly like this:

      inews (really frontend_inews)
        |
        | The article is turned into a mail message by inews.
	|
  mail comp.whatever,...
        |
        | at this point proper return addresses are on, etc.
	|
   usenet transport agent
	|
	| NNTP (or mail to feednews@news-server)
	|
  news-server.csri
	|
        |  NNTP server (if mail to feednews, alias that pipes to server_inews)
	|
    server_inews (figures out if group is moderated and so on)
	|
 	|
	|
     relaynews (actual posting)