> The number of subscribers just max out our UNIX sendmail. We are
> experimenting to use NT LSMTP to diliver our UNIX Listserv mail.

You could also try qmail, http://www.pobox.com/~djb/qmail.html,
currently at version 1.00.  It has a secure design, runs quite fast on
Unix systems, delivers mail reliably, etc., and it's free.  At least one
LISTSERV site is using it to make ~600,000 deliveries a day.
--
  Norm

The job is not to cover the material but to uncover it.  [George Miller]