Thanks much, Pete. As I was digging into this, might an active probe do
the job?  I would think the bounce would come back to listserv where it
could deal with it.

>At 11:34 04/01/2004 Thursday, Listserv Manager wrote:
> >One of our lists is troubled by bounces being returned to posters (not the
> >list) from cs (compuserve). An examination of the bounces reveals no
> >clues- this appears to be a classic case of subscriber address forwarded
> >to another address, and there's no common identifying information
> >(fragments of name, domain, etc.)
>
>How about a Listserv Distribute Mail to all subscribers, but do NOT use
>the BSMTP option.
>
>This would need to be sent from the site-authorized userid with an
>explanation as to why it is being sent.