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