Networking :: Get Connected To A Wireless Network That Only Allows DHCP?

I have a WET54g bridge that I am trying to get connected to a wireless network that only allows DHCP. The idea behind it is that I would like to connect the Cat6 out of the bridge to a switch allowing multiple wired computers to connect to the wireless network. The bridge will easily connect to the network once I put the WEP key in, however, there is a kink after that. When I connect the Cat6 to my computer and request an IP for that computer, it self assigns. This tells me that it is not talking to the wireless network through the bridge.

I can not find which IP address the bridge was assigned so that I can talk to it. The sub net is 255.255.240.0 which leaves quite a few possibilities. I know that the bridge is, however talking to the wireless network because the light is steady on the front of it which indicates just that. One other thing to stack on is that I know that there is a "splash page" which comes up when any computer connects. You click on the agreement and then you are allowed onto the network. How can I get my computer to talk through the bridge to the wireless network?