This is a new bug that's been reported in the last couple of days. I think it has to do with wxPython 2.5.3.x. (which I've been unaware of until now).
We only claim that it will work for 2.4.x, but according to Ragnar previous 2.5.x nonunicode-versions should run, although not look as "good".
2.5.x and Unicode is up for the next version (not the release (0.7 rc3) coming in a few days).
/Oscar