[Exim] Routing question...

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We currently have Exim 4.24 as our gateway mail server that relays to a
Spam and Virus scanning server which then relays to our internal mail
servers that host our e-mail boxes. I have a remote international
location that hosts several separate domains in which we handle mail
delivery.

We currently send/receive mail for that site over SSL between our Exim
server and a sendmail server on their side. However, they do not have
any spam and virus detection. I would like to know if is is possible,
from a single conf file to route the mail for these domains from our
Exim server to our scanning server, back to Exim then out to their
sendmail server without creating a mail loop?

To be more specific - we want to set up routes for these relay domains
based on the message origin. If the mail is coming from the Internet,
then we want to relay to the scanning server. If the mail is coming
from the scanning server, we want to relay to their server over SSL.

I am still learning how to best utilize Exim and appreciate any help or
ideas you can offer.

Thanks!
Jeff
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