Redirect Port 25 traffic

[burntend]

My company just had a minor issue which has us diplaced from our business location for three to four weeks due to water damage. Because I am resposible for the network services, I need to set up in a temporary location, and that is presenting some issues.

While we are displaced, all of the network services including email are sitting in our temp office, using a DSL connection. The major issue with that is that the ISP blocks port 25 for the DSL users, so a bit of redirection is required. I know how to change the settings in Exc2K, and the ISP is allowing us to use their servers a relays, but I cannot get inbound or outboud mail from the internet. I have looked thorugh the MS-KB, and every book I can get my hands on...can I get a few suggetsions?

I have tried changing the port 25 TCP settings on the server via regedit (to another port), but when I make these changes I get 115 errors in the event viewer and the SMTP service will not start. Our ISP, indicates that they will redirect to another port, but that they cannot connect to the port they want us to use. As well our firewall is open on this port, and allows traffic in both dirctions.

Thanks in advance