Unable to use internet Connection across

I have set up RAS on WINNT Server. I cannot access the T1 across the dial-up connection. I have full access to the local network and all resources. But I cannot access the internet or ping the router. The ip address that is assigned to the workstation by DHCP is also the address that is using for the default gateway. I need to know how to fix this so that I can access the T1 from a RAS Connection