Wireless PCI card and Mac

Trying to make an older G4 wireless. Got a linksys wmp54g PCI adapter 4.1. Installed Ralink RT61 driver. This allowed me to see my Airport express network, enter the wireless network password and connect to it. The driver said I was connected at 54mbps. Could not connect to internet. Network system preference says card has self assigned IP address. How can I get this setup to work? It seems the card is having a problem using DHCP to assign address. Tried manually assigning address, did not work. AirPort Setup Assistant does not recognize the card. I've never setup a wireless network. Maybe there's something simple I'm missing.