Disable Ambient display?

[bendingpixels]

I have an AT&T G4 and every time I get a notification my screen comes on. sometime in my pocket the screen will come on for no reason and it starts registering taps on the screen. It's really annoying. I've traced this behavior to something called "Ambient Display" which is supposed to activate the screen when you get a notification. BUT there doesn't seem to be any way to turn this off on the G4. It's supposed to be under the Display settings, but it is not there on my phone... has anybody been able to turn it off?

Thanks!
rob