Sendmail routing issues

[manulite]

I have a linux box (mandrake which is running a sendmail from which the users are currently popping their mail. Now we are setting up Lotus Notes and Domino for mail but we still want to mantain the linux box as a router and more importantly for scanning all emails for viruses. So the the setup we want is like this.

All email coming from the external network comes through the linux box(as it is doing now), gets scanned by the antivirus software, and then routed to the Lotus Domino server that is internal.

All email going external will come from the Lotus Domino server to the linux box which will then route it to our isp. I've managed to do this by adding the internal mail server address in the access file.

What i need to know is how to make sendmail route all email it receives for the local domain to the internal Lotus Domino server(after scanning)

[manulite]

in sendmail.mc

define(`MAIL_HUB',[ip.of.internal.server])

rebuild sendmail.cf and restart sendmail and voila, its sorted