Downgrading is trivial: apt-get install xserver-xorg-lts-precise libgl1-mesa-{dri,glx}:i386
This is unsupported for newer hardware, because they're not tested with the older linux/xserver, but in your case it would work. It seems some interaction with multiarch is making it fail. Multiarch was already failing to switch correctly, causing the 32-bits libs to be uninstalled. If I install enough 32-bits applications I can make it uninstall kubuntu-desktop too. But the failure the other way around is easier to test: pbuilder-dist precise amd64 login apt-get install --install-recommends ia32-libs xserver-xorg-lts-precise apt-get install --install-recommends xserver-xorg-lts-quantal Notice that ia32-libs gets removed by installing xserver-xorg-lts-quantal. However if I install ia32-libs afterwards it works, because that case was fixed in #1130419: pbuilder-dist precise amd64 login apt-get install --install-recommends xserver-xorg-lts-quantal apt-get install --install-recommends ia32-libs It's still easy to make the resolver die completely, too: pbuilder-dist precise amd64 login apt-get install --install-recommends xserver-xorg-lts-precise apt-get install --install-recommends xserver-xorg-lts-quantal ia32-libs if you add libgl1-mesa-{glx,dri}-lts-quantal:i386 to the last line, it will find the correct solution. -- You received this bug notification because you are a member of Ubuntu-X, which is subscribed to xorg-lts-quantal in Ubuntu. https://bugs.launchpad.net/bugs/1134492 Title: xserver-xorg-lts-quantal breaks Kubuntu To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/apt/+bug/1134492/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~ubuntu-x-swat Post to : ubuntu-x-swat@lists.launchpad.net Unsubscribe : https://launchpad.net/~ubuntu-x-swat More help : https://help.launchpad.net/ListHelp