Each LISTSERV article  is uniquely generated by a  message-ID, either the
one  in the  original (sender's)  header or  one generated  by the  first
LISTSERV (I mean  peer) to process the message.  However, this message-ID
is a "hidden" tag so you need SET listname FULLHDR to see it.
 
Now  of course  if the  NETNEWS gateway  were to  post the  same item  to
LISTSERV several times,  it would be distributed several  times, too. The
gateway must see to it that duplicates are eliminated.
 
  Eric