For several reasons I with an R40 ThinkPad and a friend with an R51 and T43P ThinkPad settled on not trying to push toward wireless connections with the available built in hardware for that.  We both originally totally successfully using LinkSys WRT45G Wireless Bridge units a long time back.  Disaster hit.  Here total connection interface to a public wireless network in her RV park went re-config after a complete direct lighting hit on the RV park admin building.  Mine partially blew up when my own private encrypted wireless network I enabled here shifted 'successfully' to complete new vendor IP operations via my onw LinkSys WRT54GL unit.  It works perfectly with hard wired network units tied to it.