Hey,

I've got two Postfix servers in my lan:

server1 has IP 192.168.1.101
server2 has IP 192.168.1.102

Both servers are sitting behind a m0n0wall router with two WAN 
interfaces. Emails designated for WAN1 is NAT'ed to server1 and email 
designated to WAN2 is NAT'ed to server2.

This works like a charm - until server1 tries to send an email to 
server2, or vice-versa. I can see in my logs that server1 obtains the 
correct WAN IP for server2, but it is refused (by m0n0wall?) to connect.

Now the optimal solution would be to create a hosts file on each server, 
telling them which domains are local, but seeing as I've had no luck 
getting Postfix to read this hosts file, I'll settle for the next best: 
opening up my m0n0wall for such a connection.

But how to do it? I simply have NO idea as to how I can create such a 
firewall/NAT configuration.

If some kind soul could help me out, I would really appreciate it.

Thank you,
Thomas