>This would require more overhead, I'm sure, but it might be made a
>user-specifiable option (some keyword in the mail header or text of the
>posting?).
More importantly, how is LISTSERV@FOO supposed to know that LISTSERV@BAR
sent you the same posting for another list they have down there and that
it knows basically nothing about? This can't be solved by having the
servers exchange this information over the network: it might not reach
the destination in time, actually if you do 'MAIL XYZ@FOO ABC@BAR' the
information from LISTSERV@FOO to LISTSERV@BAR that message X has already
been sent to user Y is very unlikely to reach LISTSERV@BAR *before* your
original message.
Eric