Connection problem : ADSL Internet -> Win2K Server -> internal Network

I have a Windows 2000 Server with two NIC's which I want to set up VPN on.
The Internet connection is an ADSL line connected to a Netopia Gateway.
The Netopia Gateway provides DHCP,NAT and DNS services to the Windows 2000
Server (on one NIC).
I can browse the web etc from the Server but none of the internal network
clients can get out.
They can all see the Win2K Server (both NIC's) and the Netopia gateway.
The Win2K Server provides DHCP for the internal network. Both NIC's are on
seperate address ranges.
The intention is to provide VPN over this interface but right now, I cannot
even connect to the outside world.
I would appreciate any suggestions as to what might be missing or
misconfigured.
On the Win2K Server, I am providing DHCP, RRAS, DNS Forwarding and NAT for
the internal network.

Thanks

Don

I found the problem.
For anyone interested, the solution lay in reconfiguring the firewall to
allow incoming packets get to their destination.

Now for the VPN!

Don