Comment 1 for bug 266959

Where did you get a 1:7.4~1ubuntu1.1 package? http://packages.ubuntu.com/intrepid/x11-common shows only 1:7.4~1ubuntu1 as available (which I was able to successfully install on my system.)

Also remember to always attach your /var/log/Xorg.0.log when reporting bugs against Ubuntu's X.org.