exchanger server

We are changeing our Network tcp/ip addresses from a Class B to a Class C. We have an Exchange Server (on NT server) that communicates with a router (with an ISDN), that is connected to our ISP. This is how we send and recieve our emails. We will change the IP address, Gateway address in the NT portion of the server. Is there any part of the Exchange Server software that we have to change the IP and Gateway, if so where are these settings ?

Thanks very much

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