There was a bug in one of the version of 1.5n (it was in the base code, I can't remember if it got fixed in FIX15N1, FIX15N2 or later) which prevented LISTSERV from actually rejecting mail from users which have been SERVEd OFF. There was also a change made sometime between 1.5n and 1.5o where LISTSERV no longer serves off its mailer, although for performance reasons it did not SERVE it back ON unconditionally after every command. At some point, with one of the changes and not the other one, it was possible to get mailer SERVEd OFF and have anything coming from it ignored by LISTSERV. I don't know how many sites are affected, but at least 2 were (UIUCVME and NDSUVM1). The fix is very simple, issue a QUIET SERVE MAILER command once, it won't (well shouldn't) get SERVEd OFF any more. To solve the problem I have sent a 1-line file with QUIET SERVE your_mailer_id@yournode to all the registered LISTSERVs, so you shouldn't have anything to do about it apart from notifying me if it happens again. Considering the number of invalid mail items we get every day at CEARN from the EAN, UUCP and DECNET gateways, and the fact that it didn't happen there in 3 days of continuous operation under 1.5o, I seriously doubt it will affect you :-) Eric