Domain Login From Another Subnet

This may be really obvious for you NT gurus out there, but I’m having trouble getting Win95/98 machines to authenticate to our Windows2000 domain when the machines are in a branch office and, therefore, on a separate subnet. We’re all connected via Frame Relay and Cisco routers. There’s no server at most of the branches, while a couple have NT4 servers (only one is a domain controller for their local office).

Am I missing something?