Eric, would you consider letting "super-users" at a site unsub a LIST
from that site?   You might reserve the userid of who you considered
a superuser and not let such a person subscribe.  That would quickly
pick up a misallocation of the id (I hope).   Dave
 
Dave Gomberg, role model for those who don't ask much in their fantasy lives.
GOMBERG@UCSFVM  Internet node UCSFVM.UCSF.EDU             fax-> (415)731-7797