You could have the copy of DOMAIN NAMES that LISTSERV@UBVM uses route
 the various domains to different places.  That is, send .COM entries
 to the local SMTP server, send .EDU entries to another server, and
 .GOV someplace else...  Yes, it's gross, but it would divide the 8k+
 recipients into at least a few chunks.  There are 63 entries for
 domains serviced by SMTP@INTERBIT in DOMAIN NAMES, although I'd guess
 that the majority of your subscribers fall into a handful of those.
 So, if you're going to try this method, you'll have to find an SMTP
 gateway willing to handle rather large bundles of mail I'd guess.
 
 -jj
 
 PS - This is what an ex-coworker of mine used to call "a nasty hack". :)
 
 PPS - I'd invite comments from other people on the pro's/con's of doing
 something like this.  I've posted it since it's the only thing that comes
 to mind for splitting up the traffic.