[Exim] Stopping host lookups?

Hi folks,

I've combed the FAQ and the docs, but I'm still stumped.

Is there any way to have Exim relay mail from our customers even when they
are assigned IP addresses (we use a few wholesale port providers) that do
not have proper host name resolution in the DNS?

We are using "host_accept_relay" to open the servers for relaying by our
dial customers. Does this force DNS lookup?

Drew Linsalata
EQUINOX Internet Services Corp.
http://www.equinox.net