If your mail server responds "appropriately" to the SMTP RFC821 dialog,
then LISTSERV sites that have generated e-mail to you should automatically
delete those users.
Otherwise, the site's NAD can issue a
DEL * userid@site
There might be a magic-cookie dialogue that takes place
though depending on the lists' level of security (* VALIDATE=).
A site's NAD can be defined in the BITEARN NODES db, or
POSTMASTER userid (as well as one or two others). There
may be a non-BITNET file that defines who they are (SERVICE?).
/Pete Weiss