[Exim] Whitelisted users

This message is in MIME format. Since your mail reader does not understand
this format, some or all of this message may not be legible.
--
[ Picked text/plain from multipart/alternative ]
I am getting a ton of messages rejected because it can't verify sender...
how do I set up a list with address that are acceptable?

I guess I am looking for how to setup a whitelist... but alas... I just
setup exim 2 days ago and don't understand how to.

Thanks for any help anyone can give me!

-Tom

--