[Exim] problem relaying

Hi,

I have just installed exim and most things are going well. However,
some people are getting relay denied even though they are in our
relay_from_hosts. I have tested other people and relay_from_hosts
successfully accepts them when they are in it, but not when they are
not.

Here is an example rejectlog entry:

2003-10-24 12:11:39 H=(elm4) [209.58.xxx.xxx] F=<xxxxx@???>
rejected RCPT <xxx.xxxx@???>: relay not permitted

The IP address is in our relay_from_hosts. (Note: reverse DNS does
not work for the address.)

Also, if I try to send something from a private subnet (on a different
network):

2003-10-25 18:41:57 H=xxxxxx.ne.client2.attbi.com (192.168.100.231)
[65.96.160.xxx] F=<dkesh@???> rejected RCPT <xxx@???>:
relay not permitted

The 65.96.160 address is in relay_from_hosts, and when I send from the
machine that's directly at that address, it relays fine.

Any help?

Dan Keshet