To Reverse / Fix
If you are using KDE 3.5 in Jaunty, you reverse this change to normal behavior by adding this code to your xorg.conf:
KDE 4Section "ServerFlags"
Option "DontZap" "off"
1) Install the “dontzap” package (hopefully this step can be skipped in the future):
sudo apt-get install dontzap
2) Launch “systemsettings” and select the “Display” module
3) Click on the checkbox labeled “Ctrl+Alt+Backspace restarts the xserver” and press the apply button.
After that, type in your password. You know the drill.
Sometimes I wonder about things like this begin cropping up in future releases. But honestly, as far as I am concerned, so long as I have the power to re-enable whatever feature was taken away, I don't see a problem here. Others may disagree, but overall I feel confident that this will be a non-issue.