okay erm. Try changing your Non-unicode to Japanese first.
Go to Start > Control panel > Regional and Language Options > Advanced tab > change the box near the top to Japanese.
If you don't have the option there, go to the Languages tab right next to it, and check the box that says "Install files for Eastern Asian Languages". You'll need your Windows CD to do that, in case you don't have it, download this. MEGAUPLOAD - The leading online storage and file delivery service