PowerPC :: IBook G4 Cannot Detect Wireless

I used to have an old iBook G4 whose hard drive conked out on me a few months ago. I sent it to Apple and go a new hard drive installed. This model of the iBook does not have the wireless built in but I got a free Airport card during the purchase and its put in. Now, I've installed Panther on it but a problem I've noticed is that I simply can't detect any wireless networks. I can turn on and off the wireless in my menu bar but whenever I search for networks, it detects nothing. This is all the time of course, next to my iMac and Powerbook which have no problems detecting the network. I've tried re-installing the OS even.