Well, this has been bugging me for quite a while on the Droid 4 (backlight turning on and off no matter what the external light source is).
I may have found a solution:
An app called Q2 backlight controller. Fairly new in the play store (January 2013).
There no user comments yet and I am hesitant to install something unproven, but permissions are ok and a scan with Lookout didn't set off any alarms.
You need root and busybox installed. Tapping the home screen icon brings up a dialog where I can turn the keyboard backlight and/or the home row button light on and off.
Closing the keyboard turns the keyboard backlight to the off position, which is great.
But the backlight for the home, back, menu keys is either on or off with this app, meaning: If set to "on" they stay lit all the time even when the screen is off.
A little cumbersome but beats trying to type in the dark! :sly:
So far it works perfectly.
Edit: After using it for a few days I am not sure I will keep Q2. It is very cumbersome to have to use the app to turn on/off the backlight for the home row keys. It it had a switch just for the keypad, it would be good, but with this app installed you have to turn on the light just to be able to see your "Home, Menu, Back and Search" keys in the dark. And each time you turn on your phone, you get that notification: Q2 has been granted SuperUser permission. Very annoying...
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