Ubuntu: "Editable Menu Accelerators" (on a per app basis). Where is this option?
Solution 1:
It seems that GNOME decided to remove the interface tab because "basically everything there is a user experience design cop-out. It only belongs in a tweak UI tool." So now the only way to enable that option is hidden deep in the gconf settings.
Launch gconf-editor from the terminal or the "Run Application" dialog (Alt-F2).
Navigate to desktop>gnome>interface and check can_change_accels
Or just run this line in a terminal:
gconftool --set /desktop/gnome/interface/can_change_accels --type=bool True