Files with unicode characters in file names (for instance "��" aren't supported. The same goes with some ordinary strings too. The international characters all gets converted to "?".
I've investigated the matter and it seems to only happen when running Java programs with the Jar launcher (i.e when double clicking jar files). The system property "sun.jnu.encoding" for instance gets incorrectly set to US-ASCII, while it should be set to UTF-8, and so it does when running the software using the command line in the java -jar jarFile format.