G4 via WPA to AD Radius server

We are having a problem were we have G4 powerbooks using
wireless however they will not authenticate correctly. An
example is that we try to connect via wireless to the wireless
router we have via WPA and it comes back saying authentication
error. Currently we are running to linksys routers both using
WPA Radius. Our Radius server is a Windows 2000 DC. Does
anybody have any idea’s on what to do?