>Serve out a subscriber's address???  How would that affect him on our
>list and the others he is probably subscribed to on the same system?

I think Jacob was looking at this from the standpoint of a user who
is being spoofed onto lists but doesn't otherwise have subs on your
system.

You could use this solution, however, for a short period with the
user's consent in order to trap a few of the messages with full
headers (they would end up in the postmaster's error queue).  Naturally
it would inconvenience the user but the question is, how inconvenienced
is he already and how much does he want this to stop?

Nathan