My company uses TrendMicro's Interscan Viruswall for our email gateway. Right now, it is running on a dedicated machine with an internal address of x.x.x.11. Our website runs on a machine with an internal address of x.x.x.4. Our Pix directs port 80 & 443 to x.x.x.4 and port 25 to x.x.x.11.
I want to decommission the dedicated Interscan machine and move the gateway to my webserver box which has dual NICs. I have reconfigured my Exchange SMTP virtual server to use port 26 internally, and have configured both my old Interscan boxes to forward mail to Exchange on port 26.
I have been able to recieve incoming email OK in this configuration, but have not been able to get outgoing to send from the webserver. It seems that the machine wants to send using the x.x.x.4 NIC which our Pix is blocking. Short of changing my firewall rules, is there a way to tell Server 2003 R2 to use NIC x.x.x.11 for port 25 traffic and x.x.x.4 for web traffic?