The inital release of MOZ is only able to parse ASCII strings. However, there is no limitation, at all, in the program that causes this to be the case; it is merely due to the definitions of 'letter' and 'number' in the ParserMonads class.
The MOZ has been shown to pass UTF-8 untouched when players say something, for example. I, personally, know nothing about any character sets other than ASCII, which is why I haven't changed the parsing. If someone else wants to do localization for a language that uses a more complicated character set, I would love to see the results, and incorporate them into the main distribution.