Arash, that seems to be a different issue. Does gnome-panel still crash when you add an xpenguin applet? If it does, please can you file a bug against xpenguin?
https://bugs.launchpad.net/ubuntu/+source/xpenguins/+filebug -- Gnome Panel applets crashing https://launchpad.net/bugs/80799 -- desktop-bugs mailing list desktop-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/desktop-bugs