Internal SMTP Relay with EXIM

[Ken McCord <ken@themccords.com>]

Hi,

I'm trying to set up an internal SMTP relay/gateway for all email on our 
network (example.com - for example).  Any Internet email should pass 
through our firewall and be forwarded to this box.  After processing 
(using exim, spamassassin, sophos), it should then be relayed to our 
GroupWise server for delivery.  Any outbound email should go the other 
way (from GroupWise to gateway, and out through the firewall).

Unfortunately, during testing I've either gotten Internet email bounced 
back to my Yahoo! account (normally '550 relaying to test@example.com 
prohibited by administrator' errors), or abuse.net says it's a possible 
open relay at step #6 (sending from example.com to example.com gives a 
deferred message).  I've followed the howto instructions included in the 
spamassassin package, but I think I'm missing something on the Exim 
configuration.

If someone has set up a similiar system, could they give me a hand?

Thanks,

Ken McCord