While  your  terms are not quite precise, it sounds like you want your
outbound  gateway  to defer accepting messages until it can be assured
that  the  next-hop  MX  will  accept  the  message.  This  simply  is
impossible  in  any multi-hop SMTP scenario, by the very definition of
SMTP.

The  only  way  to  approximate  what  you are describing is to use an
outbound SMTP *proxy*, not a full-fledged gateway. If the proxy can do
in-line  content  scanning,  it  can  reject the message based on spam
concerns  or proxy the remote MX's rejection back to your Notes server
during  the  same SMTP conversation. In sum, if you use a proxy, there
is  no  additional hop, so there will not be bounce notifications sent
between the outbound proxy and the Notes server.

--Sandy

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Sanford Whiteman, Chief Technologist
Broadleaf Systems, a division of
Cypress Integrated Systems, Inc.
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