Ive got a Postfix/Courier box in production and its working great (thank you Falko!) One little problem Im having is that the box has an external and internal interface. It accepts mail on the external interface just like it should, but when sending mail out it sends through the internal interface to my firewall and out. I have ran into bounce backs because the header information shows the NAT of my firewall. I need the mail to be handed out and accepted through the external interface when not desitned for any of my virtual users so reverse DNS lookups dont fail. Any ideas? Thanks in advance.