Why does my PSP not detect my Linksys Router?

I have a PSP Slim .. I just recently bought a new Router [ Linksys WAG120N ] .. In the wireless security section in the router setup .. my security mode is set to WPA Personal %26amp; it has a TKIP or AEP encryption .. i've even tried entering the mac address but it still does not detect the router .. can somebody please help|||usually an option to turn on the wireless seperatly in there somewhere too so you can use only a wired connec and turn off the wireless (for people like me that don't apprechiate wireless, wired is better and faster and more secure).