So maybe Wx is Unicode-enabled, but it's not as easy as it seems to use UTF-8 character encoding. I got a Japanese translation for pType from Tatsuhiko Miyagawa, tried to use it with Locale::Maketext::Lexicon and later with Wx::Locale, but neither gave the japanese characters in the menus and dialog boxes. And it's not the file that is the problem, because everything looks fine in poEdit and UltraEdit. So there must be something with internal translation stuff...
This weekend I gave the pVoice site a big update. I renewed the style and contents both. This morning I added an extensive installation instruction for the Microsoft Agent, which is a vital part of pType and will become the base for pVoice 2.0. If you're going to use Win32::MSAgent, it also may be a big help.
Now on with pVoice 2.0
Maybe you need to feed Wx consistent encodings? Have you tried passing it all languages in UTF-8 (truly encoded thus, and if possible with the proper Perl flag on)? Or maybe you need to clearly mark the Japanese content as UTF-8? Such a behaviour would not surprise me.