[Exim] How to do SMTP AUTH on a smarthost?

Hi all,

I am using a cluster of Exim 4.x machines to front-end my main mailhost,
which never appears in the MX records for the domains I handle mail for
(the exim boxes do all the mail processing and then passes it on to the
main mailhost via a smart route). At the moment, our users send out/relay
mail through the main mailhost which runs CommuniGate Pro. I want to shift
this duty to the exim boxes. The problem is that no local accounts exist
on the exim boxes, so I need a way to handle SMTP AUTH for those folks that
are not on our trusted IP blocks. I suspect I'll need to use an ACL, but
I'm not sure how to do some sort of callback or something to CommuniGate
Pro for SMTP AUTH.

Any pointers?

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Mike Bacher / isp-list@???
TCIS - TulsaConnect Internet Services
Phone: 918-584-1100x110 Fax: 918-582-5776
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