http://forum.pentaxfans.net/forum.php?mod=viewthread&tid=135078
(in Traditional Chinese)
For those special versions that sold in particular countries/regions, e.g. in Japan, the K-01 has only Japanese and English selectable as the user menu language. Someone in Taiwan has discovered that the local language menu can actually be unlocked and unleashed simply via the Debug mode.
What to do is to enter the Debug mode by using the PK Tether. After that, the local language option will appear. Just select it and leave the Debug mode. That's it! You have a local version of the K-01 body after that, then! Is that great enough? Yes, it really is!
If this trick really works, just don't feel hesitate to buy a Pentax camera in Japan where it could be cheap enough for some discounted models. Good luck next time when you travel there!
Btw, if you try this and succeed, please tell us and confirm it here! :-)