These 4 bugs seems to be related, or are the same one. bug612620 Fade-out to screensaver cannot be interrupted
with xorg-x11-server-Xorg-1.8.2-1.fc13 bug615786 As screensaver activates and screen dims cannot intervene
with mouse/keys bug620186 The fading of the screen when GNOME screensaver start is
not interruptible bug620264 gnome-screensaver activates whether or not activity occurs
once dimming starts
These 4 bugs seems to be related, or are the same one. server- Xorg-1. 8.2-1.fc13
bug612620 Fade-out to screensaver cannot be interrupted
with xorg-x11-
bug615786 As screensaver activates and screen dims cannot intervene
with mouse/keys
bug620186 The fading of the screen when GNOME screensaver start is
not interruptible
bug620264 gnome-screensaver activates whether or not activity occurs
once dimming starts