Right, WinMo != Windows. It's a nasty work-alike with the same name slapped on it. To make WinMo display/input anything other than english it takes a bit of work. I managed to bash WinMo 4.3 into working with Japanese, but it was flaky.

Maemo runs the same Linux that your desktop PC can, which uses UTF-8 systemwide, I suspect that display will be system wide and problem free, while input projects are currently in progress.