Try sending
 
SERVE MAILER@UTORGPU
 
to LISTSERV.
 
Apparently MAILER@UTORGPU has been bad and sent more than the limit of
erroneous commands in a row to LISTSERV.
 
On the other hand--MAILER@UTORGPU may well have been served out for a
reason.  You might want to check with the LISTSERV postmaster first.
 
Nathan