On a previous version of Ubuntu/Gnome, I used to have alt+shift toggle the keyboard layout and alt+shift+tab do the same as alt-tab but in the opposite direction. Right now, I can't do this: If alt+shift is enabled to change the keyboard layout, alt+shift+tab will not work (it'll act as if I had just pressed alt+tab). I'm almost sure that before, the keyboard layout would not change until I let go of alt (so, alt+shift keydown would do nothing, alt+shift and then keyup of shift would change the language). How can I fix this?
This bug exists for several distributions (including Debian). The way to fix it is to use Ubuntu's patch to fix xorg-server's xkbActions.c file.
This is the patch for version 1.12.4-6: http://pastebin.com/m4NasCiy