On Wed, 12 Aug 1998 11:53:33 EDT, you said:
> > <[log in to unmask]>:
> > 207.51.47.2 does not like recipient.
> > Remote host said: 550 <[log in to unmask]>... User unknown
> > Giving up.

A bit of quick digging shows the following:

1) 207.51.47.2 has a PTR entry to 'ultima.thenerve.com'.
2) lists.rferl.org has an MX and an A record pointing there.

Summary:  Contact [log in to unmask] and complain about
their user.  Apparently, rferl.org is being hosted by thenerv,com, and
somebody downloaded the Listserv evaluation kit and (a) forgot to
tell LSoft so they aren't in PEERS NAMES, and (b) forgot to tell
thenerve.com management to add the Sendmail aliases for Listserv and
the lists....

--
                                Valdis Kletnieks
                                Computer Systems Senior Engineer
                                Virginia Tech