Version: (using KDE 4.1.2) OS: Linux Installed from: Ubuntu Packages When I switch off the laptop, using the kde menu item "éteindre" (in French), the screen change black, after a few seconds, a dialog box appear saying kwin has crashed. Then I click on "ok". After that only, the splash screen (from kubuntu) appears, meaning the computer is really shutting down. I have a kwin.kcrash file I can give you.
Created attachment 28447 [details] the bug report producted by the software itself.
*** This bug has been marked as a duplicate of bug 163538 ***