Dan:
 
I'd like to recommend the following steps:
 
1) Start LISTSERV but then immediately issue the command
 
   HOLD CDROMLAN
 
2) Alter CDROMLAN headers to SEND= PRIVATE (at least temporaily)
   and FILTER= ALSO,POSTMASTER@*,POSTMAST@*
 
3) SET CDROMLAN NOM NOF FOR [log in to unmask]