[exim] redirect+change To: field

Helo,

I have some data in myslq database.

incoming1@testdomain : out1@otherdomain
incoming1@testdomain : out2@otherdomain
incoming1@testdomain : out3@otherdomain

When someone sends an email to the incoming1@testdomain it gets
redirected to those other 3 addresses.

What i want to do is change the To: field to contains address that the
email is currently transported to.

I could use headers_rewrite (in remote_smtp with smtp driver), or
headers_add in router, but i need the variable where the currently
processed e-mail addres is. To get proper lookup.

Any ideas how to achive such thing maybe in a different way?

--
Mc.
$:It's kind of fun to do the impossible.