Comment 8 for bug 86103

I too encounter the above problems. There's not much material available online, but the problem seems to be bound to the version of xlib/x11 in feisty (though it might not be a bug in xlib). I'd consider this to be of really high importance - there's quite a lot of java gui programs out there and chances are that most of them won't work (at least if they somehow make use of awt/swing)