RAS and DHCP

We have a server running Win2k Server which runs DHCP. There are two NICs installed. One runs to the network, the other directly to the cable modem router. We have a static IP and are trying to get VPN started. However, everytime we configure RAS, DHCP stops releasing IPs and error “64” is recorded in the DHCP log. We have already checked the bindings and the DHCP relay agent points to the adapter that DHCP is binded too. Any help would be greatly appreciated!