This one is difficult. When using java.io.File class Sun VM and gcj produce different results. If create a file name which contains for example Russian Letters in it (you can do this: open IE and go to the www.rambler.ru then add this link to the Favorites. Now open the dir:
File dir = new File( "C:\\Documents and Settings\\<user>\\Faforites" ); File [] files = dir.listFiles(); for( int i = 0; i < files.length; i++ ) { String name = files[i].getName(); if( -1 != name.indexOf( "rambler" ) ) { // here you can try to open and let's read it, it will fail in GCJ // but not in SUN VM. } } . -- Summary: Non-English File Names processed incorrectly in Windows. Product: gcc Version: 4.0.0 Status: UNCONFIRMED Severity: normal Priority: P2 Component: libgcj AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: mnefedov at rogers dot com CC: gcc-bugs at gcc dot gnu dot org,java-prs at gcc dot gnu dot org http://gcc.gnu.org/bugzilla/show_bug.cgi?id=21267