Hi i have 2 mail servers which I hoped to run behnd NAT but so far have not been successful. They can be seen on the public IPs but not from the LAN using public IPs. As a workaround I have placed the 2 servers in the DMZ and things are better. The only problem now is the 2 mail servers are not talking correctly they can ping each other on the public IPs but trace route times out from one to the other and SMTP also times out. On the private IPs everything works fine.

Any help would be very much appreciated as mails are getting stuck and I have to use the old efficient 5861 router to clear them down. External emails coming in to each server all work perectly.

Make sure that the public IPs you're using for the 2 mail servers aren't in the WAN IP Alias table for multi-NAT (the button on the WAN/Internet Access page).