Also, on the client side,make sure you are using the correct "base:" if you are entering numbers like "00 20 5c e5 d6..." then MAKE SURE the client is NOT set to ASCII...it should be "Hex digits" (or whatever)...NOT ASCII. Also make sure you are setting the right keys. The ORinoco Silver is only a 40 bit card, the 340 can do 128...that means you would have to enter TWO keys on the Aironet base (one for 40 bit, one for the 128). The keys are case sensitive (if you're using ASCII keys).
(for those that haven't seen it: the XP wireless client lets you enter the keys as ASCII or Hex, 40 or 128 bit, the Orinoco cards & setup want to use ASCII real bad...they show five numbers, but it's really five ASCII charactors that happen to represent numbers).
FWIW
Scott