WIN 98 & DEFAULT GATEWAY PROBLEMS

I am setting up 25 win98 clients on an nt 4.0 network. They get their IP addresses dynamically assigned using DHCP. That part, works fine. The clients are able to get onto the network and browse no problem. When I enter the default gateway on the workstations and do an ipconfig, the default gateway doesn’t show up. It’s like I’ve done nothing. Now, When I give the clients a static ip address, and do an ipconfig, then the default gatway shows up fine and they are able to cruise the internet. Is there something I’m misssing within DHCP? I would like to use DHCP and still retain the default gateway. Thanks!