Sometimes when I let my MBP (see sig) go to sleep with the screen open, I come back and hit the spacebar to wake it up and it doesn't give me the password dialog box to wake it from sleep. All i see is a black screen with the mouse pointer on it. This sometimes happens when I wake and DO get the password box but if I wait and don't enter the password right away, the box disappears and wont come back. In both cases I'm forced to push the power button to shut it down and restart. Any solutions to this, or is it just a fluke?