Opensuse 11.4 x86_64. GTK3 interface is showing it.
Log:
zenitur@linux-athlon64x2:~> fceux
Starting FCEUX 2.2.0...
(fceux:18490): Gtk-WARNING **: GamepadConfigAction: missing action GamepadConfigAction
zenitur@linux-athlon64x2:~> cd fceux-2.2.2/bin/
zenitur@linux-athlon64x2:~/fceux-2.2.2/bin> ./fceux
Starting FCEUX 2.2.2...
(fceux:18599): Gtk-WARNING **: GamepadConfigAction: missing action GamepadConfigAction
(fceux:18599): Gtk-CRITICAL **: IA__gtk_check_menu_item_set_active: assertion `GTK_IS_CHECK_MENU_ITEM (check_menu_item)' failed
I found same bugreport in other project: https://bugs.launchpad.net/ubuntu/+source/camorama/+bug/992730
This applies to 2.2.0 and 2.2.2.