Screen turns on when plugged or unplugged charger, won't turn off

[rrand]

This just started happening. When the screen is off if I plug in or out the charger, the screen comes on. It stays on. It used to shut off on it's own and not turn on when the charger was used. In settings > applications > development, Stay Awake is unchecked. Does anyone know how to fix this? It might have happened after I installed Juice Defender but I uninstalled it but it didn't help. TIA.