I have a Dell Optiplex GX520, purchased here in Japan, on which I have installed an English version of Windows XP (SP2). This model only accepts a USB keyboard, and the Japanese one that shipped with it is being recognized by the OS as an English keyboard (in terms of key placement).
Let me say: I know all the basics and have configured hundreds of such systems. I know how it is *supposed* to be setup and have never had any problems until now with this new Dell model. I have tried various text input/keyboard settings (Japanese, Natural Input, MS IME 2002) and none of them give me the right keys in the right places.
I also bought a different Logicool keyboard to see if it was a simple driver error but no joy. I still get the English layout even though the system says it should be otherwise.