ICS and SBS 2000

I just installed Windows 2000 SBS with active directory. I need to use the ICS for a dial up connection, but when I enable it, the DNS proxy agent errors out, preventing the clients from initiating dial on demand, although they still have internet access, if the connection is initiated from the server. ICS is the only DHCP server running. Need a suggestion on preventing the DNS server's proxy agent from conflicting with the ICS.