[Exim] Rewrite a domain before ACLs are run?

I need to do a simple domain rewrite, e.g.

joe@??? -> joe@???

..via a MySQL lookup (the table contains a field called aliasof that I use
to substitute in as the rewritten domain).

I can do this via the "rewrite" area of the config just fine. The problem
is, I need this done before any ACLs are run, so anything passed to the
ACLs in the $domain variable will contain "domain2.com" per above.

Any pointers?

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