Java's been broken on Hardy Heron for a while, but I just upgraded to Alpha 5 and found out for myself :-(

The symptoms of the bug are a crash with an error message that contains:
xcb_xlib_unlock: Assertion `c->xlib.lock' failed.

At Dave Shucks blog, I found a patch that works:


LIB_TO_PATCH=libmawt.so
for f in `find /opt -name "$LIB_TO_PATCH"`
do
echo "Patching library $f"
sudo sed -i 's/XINERAMA/FAKEEXTN/g' "$f"
done


Where "/opt" is a directory where you keep your JDKs.

The fix is widely available on the internet, but I thought it was worth restating here.