Problem spontaneously disappeared with today's "aptitude update && aptitude full-upgrade".
The ibus error message is still here. So this was indeed unrelated. Strangely enough, today's update did not include xorg packages. My best guess is that the problem was in some KDE base package. Exact list of today's upgrade is: ============= The following NEW packages will be installed: network-manager-pptp-kde The following packages will be upgraded: app-install-data bluedevil bzip2 flashplugin-installer gstreamer0.10-pulseaudio kde-window-manager kdebase-workspace kdebase-workspace-bin kdebase-workspace-data kdebase-workspace-kgreet-plugins kdm kinfocenter klipper kpackagekit ksysguard ksysguardd kubuntu-desktop lib32bz2-1.0 libbz2-1.0 libgc1c2 libkdecorations4 libkephal4 libkscreensaver5 libksgrd4 libksignalplotter4 libkwineffects1a libkworkspace4 libpackagekit-glib2-14 libpackagekit-qt-14 libplasma-geolocation-interface4 libplasmaclock4b libplasmagenericshell4 libprocesscore4a libprocessui4a libsolidcontrol4a libsolidcontrolifaces4 libtaskmanager4a libweather-ion4a linux-headers-2.6.35-22 linux-headers-2.6.35-22-generic linux-image-2.6.35-22-generic openoffice.org openoffice.org-base openoffice.org-base-core openoffice.org-calc openoffice.org-common openoffice.org-core openoffice.org-draw openoffice.org-emailmerge openoffice.org-filter-binfilter openoffice.org-filter-mobiledev openoffice.org-impress openoffice.org-java-common openoffice.org-kde openoffice.org-math openoffice.org-officebean openoffice.org-report-builder-bin openoffice.org-style-oxygen openoffice.org-writer packagekit packagekit-backend-apt packagekit-backend-aptcc plasma-dataengines-workspace plasma-desktop plasma-netbook plasma-scriptengine-python plasma-widgets-workspace python-apt python-packagekit python-software-properties python-uno software-properties-kde systemsettings ttf-opensymbol uno-libs3 ure ureadahead ============= Should this bug report be closed? Chaosind, did the problem disappear for you too? -- KDE does not start; thrown back to login screen https://bugs.launchpad.net/bugs/638817 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs