LISTSERV also catches  signoff requests sent to the list.  The problem is
that users are  getting increasingly creative at making  up syntaxes that
don't exist  and are thus not  caught. Another problem is  the incredible
amount of  new users with signature  files of 15-20 lines.  LISTSERV only
looks for commands  in short messages, on the assumption  that people are
unlikely to  send 20 subscription requests  in a single file.  It's all a
tradeoff  between catching  the bad  commands, and  preventing legitimate
messages  from  being  posted.  I  have  increased  the  "small  message"
threshold  for the  next version,  and also  added a  couple of  the most
popular subscribe commands that don't actually exist :-)
 
  Eric