Further debugging on #ubuntu-devel has revealed that gnome-settings-daemon listens for numlock keypresses (by listening for every key event) and sets the gconf key.
I have also discovered that, snooping with xev, I see a KeyPress event for num lock when the state is off (i.e. when turning num lock on) but NOT when turning it off.
Further debugging on #ubuntu-devel has revealed that gnome-settings- daemon listens for numlock keypresses (by listening for every key event) and sets the gconf key.
I have also discovered that, snooping with xev, I see a KeyPress event for num lock when the state is off (i.e. when turning num lock on) but NOT when turning it off.
This may point to an xkeyboard-config issue...