As far as I am aware of LISTSERV technology, NO -- you can't do
anything about what and when the user's host generates.  Based
upon previous discussions herein, I don't think these are RFC-
nor mailer- compliant messages, therefore, LISTSERV passes them
on to the operand of the list's keyword * ERRORS-TO=
 
The way *I* deal with such is to have a separate account/userid
(in actuality, a private BBS gateway) listed as the operand of
the ERRORS-TO= where it does NOT interfere with my REAL e-mail
(and duties).
 
/Pete Weiss at Penn State