I have Juice Defender Ultimate installed with default settings on my Desire Z, which is running CyanogenMod7. I find that when Juice Defender is running my screen turns on every few minutes. If I stop the Juice Defender service the screen stays off. For an app that's supposed to save battery power this seems like odd behaviour. Has anyone got any idea why it needs to turn on the screen every few minutes?
So I uninstalled Juice Defender and installed Green Power instead - another battery saver. It did exactly the same thing - turning the screen on every few minutes. WTF????