Problem with the upgrade from 10.10 to 11.04

The update from 10.10 to 11.04 via the graphical interface fails. Here is the output from the main.log in /var/log/dist-upgrade:

2011-04-30 15:25:50,415 INFO Using config files '['./DistUpgrade.cfg']'
2011-04-30 15:25:50,415 INFO uname information: 'Linux Macbook 2.6.35-28-generic #50-Ubuntu SMP Fri Mar 18 19:00:26 UTC 2011 i686'
2011-04-30 15:25:50,416 INFO release-upgrader version '0.150' started
2011-04-30 15:25:51,364 DEBUG Using 'DistUpgradeViewKDE' view
2011-04-30 15:25:51,395 DEBUG aufsOptionsAndEnvironmentSetup()
2011-04-30 15:25:51,395 DEBUG using '/tmp/upgrade-rw-POhZbJ' as aufs_rw_dir
2011-04-30 15:25:51,396 DEBUG using '/tmp/upgrade-chroot-m_oJFq' as aufs chroot dir
2011-04-30 15:25:51,396 DEBUG enable dpkg --force-overwrite
2011-04-30 15:25:51,432 DEBUG creating statefile: '/var/log/dist-upgrade/apt-clone_system_state.tar.gz'
2011-04-30 15:25:55,642 DEBUG lsb-release: 'maverick'
2011-04-30 15:25:55,642 DEBUG _pythonSymlinkCheck run
2011-04-30 15:25:55,674 DEBUG openCache()
2011-04-30 15:25:56,499 DEBUG /openCache(), new cache size 32505
2011-04-30 15:25:56,500 DEBUG needServerMode(): run in 'desktop' mode, (because of pkg 'kubuntu-desktop')
2011-04-30 15:25:56,500 DEBUG checkViewDepends()
2011-04-30 15:25:56,500 DEBUG running doUpdate() (showErrors=False)
2011-04-30 15:25:58,344 DEBUG openCache()
2011-04-30 15:25:59,033 DEBUG /openCache(), new cache size 32505
2011-04-30 15:25:59,033 DEBUG doPostInitialUpdate
2011-04-30 15:25:59,033 DEBUG Plugin modules in ./plugins: remove_lilo_plugin.py dpkg_status_plugin.py langpack_manual_plugin.py deb_plugin.py kdelibs4to5_plugin.py
2011-04-30 15:25:59,033 DEBUG Loading module ./plugins/remove_lilo_plugin.py
2011-04-30 15:25:59,034 DEBUG Plugins in <module 'remove_lilo_plugin' from './plugins/remove_lilo_plugin.py'>: <class 'remove_lilo_plugin.RemoveLiloPlugin'>
2011-04-30 15:25:59,035 DEBUG Loading module ./plugins/dpkg_status_plugin.py
2011-04-30 15:25:59,036 DEBUG Plugins in <module 'dpkg_status_plugin' from './plugins/dpkg_status_plugin.py'>: <class 'dpkg_status_plugin.DpkgStatusPlugin'>
2011-04-30 15:25:59,036 DEBUG Loading module ./plugins/langpack_manual_plugin.py
2011-04-30 15:25:59,038 DEBUG Plugins in <module 'langpack_manual_plugin' from './plugins/langpack_manual_plugin.py'>: <class 'langpack_manual_plugin.MarkLangpacksManuallyInstalledPlugin'>
2011-04-30 15:25:59,038 DEBUG Loading module ./plugins/deb_plugin.py
2011-04-30 15:25:59,038 DEBUG Plugins in <module 'deb_plugin' from './plugins/deb_plugin.py'>: <class 'deb_plugin.DebPlugin'>
2011-04-30 15:25:59,039 DEBUG Loading module ./plugins/kdelibs4to5_plugin.py
2011-04-30 15:25:59,039 DEBUG Plugins in <module 'kdelibs4to5_plugin' from './plugins/kdelibs4to5_plugin.py'>: <class 'kdelibs4to5_plugin.Kdelibs4devToKdelibs5devPlugin'>
2011-04-30 15:25:59,040 DEBUG plugins for condition 'PostInitialUpdate' are '[]'
2011-04-30 15:25:59,040 DEBUG plugins for condition 'nattyPostInitialUpdate' are '[]'
2011-04-30 15:25:59,040 DEBUG plugins for condition 'from_maverickPostInitialUpdate' are '[]'
2011-04-30 15:26:03,378 DEBUG Foreign: sun-java6-jdk sun-java6-bin acroread sun-java6-jre skype sun-java6-plugin
2011-04-30 15:26:03,378 DEBUG Obsolete: libmpcdec3 synkron libisccc40 libisccfg40 applesmc-dkms libxklavier12 libcolamd-3.2.0 libavahi-core5 libpoppler4 truecrypt libdirectfb-1.0-0 plasma-wallpaper-weather libraw1394-8 language-support-extra-de evolution-documentation-de planetpenguin-racer-dbg hotkey-setup apport-qt libmagickwand1 planetpenguin-racer-data bcm5974-dkms language-support-translations-en cwp libpolkit2 googleearth-data libk3b3-extracodecs libicu38 libdns45 kde-icons-oxygen planetpenguin-racer libnm-glib0 public-transport-icons libbind9-40 libdvdcss2 libmagickcore1 python-plasma libpolkit-grant2 libkrb53 libvolume-id1 metamorphose screen-profiles evolution-documentation-en kde-printer-applet liblwres40 libamrnb3 libdbus-qt-1-1c2 libamrwb3 libboost-program-options1.35.0 libmodplug0c2 libisc45 language-support-translations-de firefox-3.5 dontzap libparted1.8-10 libgraphviz4 update-notifier-kde policykit libpolkit-dbus2 libk3b3 libntfs-3g49 install-package libao2 libxxf86misc1
2011-04-30 15:26:03,379 DEBUG updateSourcesList()
2011-04-30 15:26:03,437 DEBUG rewriteSourcesList()
2011-04-30 15:26:03,441 DEBUG examining: 'deb http://de.archive.ubuntu.com/ubuntu/ maverick main restricted'
2011-04-30 15:26:03,441 DEBUG entry 'deb http://de.archive.ubuntu.com/ubuntu/ natty main restricted' updated to new dist
2011-04-30 15:26:03,441 DEBUG examining: 'deb-src http://de.archive.ubuntu.com/ubuntu/ maverick main restricted'
2011-04-30 15:26:03,441 DEBUG entry 'deb-src http://de.archive.ubuntu.com/ubuntu/ natty main restricted' updated to new dist
2011-04-30 15:26:03,441 DEBUG examining: 'deb http://de.archive.ubuntu.com/ubuntu/ maverick-updates main restricted'
2011-04-30 15:26:03,441 DEBUG entry 'deb http://de.archive.ubuntu.com/ubuntu/ natty-updates main restricted' updated to new dist
2011-04-30 15:26:03,441 DEBUG examining: 'deb-src http://de.archive.ubuntu.com/ubuntu/ maverick-updates main restricted'
2011-04-30 15:26:03,441 DEBUG entry 'deb-src http://de.archive.ubuntu.com/ubuntu/ natty-updates main restricted' updated to new dist
2011-04-30 15:26:03,441 DEBUG examining: 'deb http://de.archive.ubuntu.com/ubuntu/ maverick universe'
2011-04-30 15:26:03,441 DEBUG entry 'deb http://de.archive.ubuntu.com/ubuntu/ natty universe' updated to new dist
2011-04-30 15:26:03,442 DEBUG examining: 'deb-src http://de.archive.ubuntu.com/ubuntu/ maverick universe'
2011-04-30 15:26:03,442 DEBUG entry 'deb-src http://de.archive.ubuntu.com/ubuntu/ natty universe' updated to new dist
2011-04-30 15:26:03,442 DEBUG examining: 'deb http://de.archive.ubuntu.com/ubuntu/ maverick-updates universe'
2011-04-30 15:26:03,442 DEBUG entry 'deb http://de.archive.ubuntu.com/ubuntu/ natty-updates universe' updated to new dist
2011-04-30 15:26:03,442 DEBUG examining: 'deb-src http://de.archive.ubuntu.com/ubuntu/ maverick-updates universe'
2011-04-30 15:26:03,442 DEBUG entry 'deb-src http://de.archive.ubuntu.com/ubuntu/ natty-updates universe' updated to new dist
2011-04-30 15:26:03,442 DEBUG examining: 'deb http://de.archive.ubuntu.com/ubuntu/ maverick multiverse'
2011-04-30 15:26:03,442 DEBUG entry 'deb http://de.archive.ubuntu.com/ubuntu/ natty multiverse' updated to new dist
2011-04-30 15:26:03,442 DEBUG examining: 'deb-src http://de.archive.ubuntu.com/ubuntu/ maverick multiverse'
2011-04-30 15:26:03,443 DEBUG entry 'deb-src http://de.archive.ubuntu.com/ubuntu/ natty multiverse' updated to new dist
2011-04-30 15:26:03,443 DEBUG examining: 'deb http://de.archive.ubuntu.com/ubuntu/ maverick-updates multiverse'
2011-04-30 15:26:03,443 DEBUG entry 'deb http://de.archive.ubuntu.com/ubuntu/ natty-updates multiverse' updated to new dist
2011-04-30 15:26:03,443 DEBUG examining: 'deb-src http://de.archive.ubuntu.com/ubuntu/ maverick-updates multiverse'
2011-04-30 15:26:03,443 DEBUG entry 'deb-src http://de.archive.ubuntu.com/ubuntu/ natty-updates multiverse' updated to new dist
2011-04-30 15:26:03,443 DEBUG examining: 'deb http://archive.canonical.com/ubuntu maverick partner'
2011-04-30 15:26:03,443 DEBUG entry 'deb http://archive.canonical.com/ubuntu natty partner' updated to new dist
2011-04-30 15:26:03,443 DEBUG examining: 'deb-src http://archive.canonical.com/ubuntu maverick partner'
2011-04-30 15:26:03,443 DEBUG entry 'deb-src http://archive.canonical.com/ubuntu natty partner' updated to new dist
2011-04-30 15:26:03,444 DEBUG examining: 'deb http://de.archive.ubuntu.com/ubuntu/ maverick-security main restricted'
2011-04-30 15:26:03,444 DEBUG entry 'deb http://de.archive.ubuntu.com/ubuntu/ natty-security main restricted' updated to new dist
2011-04-30 15:26:03,444 DEBUG examining: 'deb-src http://de.archive.ubuntu.com/ubuntu/ maverick-security main restricted'
2011-04-30 15:26:03,444 DEBUG entry 'deb-src http://de.archive.ubuntu.com/ubuntu/ natty-security main restricted' updated to new dist
2011-04-30 15:26:03,444 DEBUG examining: 'deb http://de.archive.ubuntu.com/ubuntu/ maverick-security universe'
2011-04-30 15:26:03,444 DEBUG entry 'deb http://de.archive.ubuntu.com/ubuntu/ natty-security universe' updated to new dist
2011-04-30 15:26:03,444 DEBUG examining: 'deb-src http://de.archive.ubuntu.com/ubuntu/ maverick-security universe'
2011-04-30 15:26:03,444 DEBUG entry 'deb-src http://de.archive.ubuntu.com/ubuntu/ natty-security universe' updated to new dist
2011-04-30 15:26:03,444 DEBUG examining: 'deb http://de.archive.ubuntu.com/ubuntu/ maverick-security multiverse'
2011-04-30 15:26:03,445 DEBUG entry 'deb http://de.archive.ubuntu.com/ubuntu/ natty-security multiverse' updated to new dist
2011-04-30 15:26:03,445 DEBUG examining: 'deb-src http://de.archive.ubuntu.com/ubuntu/ maverick-security multiverse'
2011-04-30 15:26:03,445 DEBUG entry 'deb-src http://de.archive.ubuntu.com/ubuntu/ natty-security multiverse' updated to new dist
2011-04-30 15:26:03,445 DEBUG examining: 'deb http://extras.ubuntu.com/ubuntu maverick main #Third party developers repository'
2011-04-30 15:26:03,445 DEBUG entry 'deb http://extras.ubuntu.com/ubuntu natty main #Third party developers repository' updated to new dist
2011-04-30 15:26:03,478 DEBUG running doUpdate() (showErrors=True)
2011-04-30 15:26:45,964 DEBUG openCache()
2011-04-30 15:26:45,964 DEBUG failed to SystemUnLock() (E:Nicht gesperrt)
2011-04-30 15:26:50,421 DEBUG /openCache(), new cache size 33785
2011-04-30 15:26:50,421 DEBUG needServerMode(): run in 'desktop' mode, (because of pkg 'kubuntu-desktop')
2011-04-30 15:28:33,357 DEBUG Running KeepInstalledSection rules
2011-04-30 15:28:34,392 DEBUG Kernel uname: '2.6.35-28-generic'
2011-04-30 15:28:34,822 DEBUG ./get_kernel_list.sh returns: ['linux-generic', 'linux-image-generic', 'linux-virtual', 'linux-image-virtual', 'linux-rt', 'linux-image-rt']
2011-04-30 15:28:34,822 DEBUG linux-generic kernel already installed
2011-04-30 15:28:34,823 DEBUG nvidiaUpdate()
2011-04-30 15:28:34,827 ERROR NvidiaDetection returned a error: __init__() got an unexpected keyword argument 'datadir'
2011-04-30 15:28:34,827 DEBUG Installing 'dontzap' (kubuntu-desktop PostUpgradeInstall rule)
2011-04-30 15:31:56,804 ERROR Dist-upgrade failed: 'E:Probleme können nicht korrigiert werden, Sie haben gehaltene defekte Pakete.'
2011-04-30 15:31:56,804 DEBUG abort called
2011-04-30 15:31:56,852 DEBUG openCache()
2011-04-30 15:31:56,852 DEBUG failed to SystemUnLock() (E:Nicht gesperrt)
2011-04-30 15:32:05,861 DEBUG /openCache(), new cache size 32505
2011-04-30 15:32:05,950 DEBUG enabling apt cron job

I already tried to solve it with using the commands

sudo apt-get update
sudo apt-get -y upgrade
sudo apt-get -y dist-upgrade
sudo do-release-upgrade

but it didn't help. Is there any other way I could try?