This bug was fixed in the package update-manager - 1:0.163

---------------
update-manager (1:0.163) quantal; urgency=low

  [ Colin Watson ]
  * Isolate tests from local configuration in
    /etc/update-manager/release-upgrades.d/.
  * Use Python attributes rather than GObject.get_data and GObject.set_data,
    which have been removed upstream (LP: #1009859).
  * Switch default view class to Gtk3 and replace python-gobject dependency
    with python-gi.
  * Port away from old-style apt.Package candidateFoo and installedFoo
    properties, preferring candidate.foo and installed.foo.  In a number of
    cases we have to check whether candidate/installed is non-None first.
  * Use apt_pkg.version_compare rather than apt_pkg.VersionCompare.
  * Use apt_pkg.uri_to_filename rather than apt_pkg.URItoFileName.
  * Use apt_pkg.TagFile (and related new-style API) rather than
    apt_pkg.ParseTagFile.
  * Use apt_pkg.PackageManager rather than apt_pkg.GetPackageManager.
  * Use apt_pkg.Acquire rather than apt_pkg.GetAcquire.
  * Use mark_foo/marked_foo rather than markFoo/markedFoo.
  * Use apt_pkg.ActionGroup rather than apt_pkg.GetPkgActionGroup.
  * Use apt_pkg.ProblemResolver rather than apt_pkg.GetPkgProblemResolver.
  * Use apt_pkg.read_config_file rather than apt_pkg.ReadConfigFile.
  * Use new spelling of apt_pkg.DepCache methods.
  * Rename several local cache methods to PEP-8 style to avoid showing up in
    the output of /usr/share/python-apt/migrate-0.8.py.
  * Use apt_pkg.size_to_str rather than apt_pkg.SizeToStr.
  * Use apt_pkg.PackageManager.get_archives rather than
    apt_pkg.PackageManager.GetArchives.
  * Use apt_pkg.Acquire.fetch_needed rather than
    apt_pkg.Acquire.FetchNeeded.
  * Use new spelling of apt_pkg.Package/Version/Dependency methods.
  * Use apt_pkg.pkgsystem_lock rather than apt_pkg.PkgSystemLock.
  * Use new spelling of apt_pkg dependency parsing methods.
  * Use new spelling of apt_pkg.SourceList methods.
  * Bump python-apt (build-)dependency to >= 0.8.0.
  * Add a scheme for excluding false positives from the pyflakes test, and
    enable it by default.
  * Rearrange the OptionParser workaround from 1:0.154.5 to work with Python
    3, using gettext or ugettext as appropriate.
  * Always pass bytes to hashlib.md5.update.
  * Fix DistUpgradeAptCdrom to account for gzip files being opened in binary
    mode.
  * Convert the last use of os.popen to subprocess.check_output, which makes
    it easier to read str rather than bytes.  (This requires Python 2.7.)
  * Decode bytes read from urlopened file objects.
  * UpdateManager/backend/InstallBackendSynaptic.py
    - Keep a reference to the data tuple passed to GObject.child_watch_add
      to avoid attempts to destroy it without a thread context
      (LP: #724687).
    - Open temporary synaptic selections file in text mode.
  * Define __bool__ rather than __nonzero__ method in Python 3.
  * sort(cmp=) and sorted(cmp=) no longer work in Python 3.  Use appropriate
    key= arguments instead.
  * Fix ResourceWarning while reading /proc/mounts.
  * Make update-manager-kde depend on psmisc, for killall.
  * DistUpgrade/DistUpgradeView.py:
    - Use floor division in FuzzyTimeToStr.
  * DistUpgrade/DistUpgradeViewText.py:
    - Flush stdout after printing confirmation message, since it doesn't
      have a trailing newline.
  * Use the appropriate Unicode gettext methods in both Python 2 and 3, and
    drop lots of Python-3-unfriendly Unicode mangling as a result.
  * DistUpgrade/DistUpgradeViewKDE.py:
    - Open the terminal log in binary mode.
  * data/do-release-upgrade.8:
    - Provide a more useful NAME section.
  * DistUpgrade/DistUpgradeCache.py:
    - Tolerate SyntaxError from attempting to import NvidiaDetector, until
      such time as a complete ubuntu-drivers-common Python 3 port is in the
      archive.
  * Switch #! lines over to python3, apart from dist-upgrader which needs to
    stay as Python 2 for a while longer (and have some special arrangement
    for running with Python 3 for upgrades from >= quantal).
  * Run tests under both Python 2 and 3.

  [ Adam Conrad ]
  * Merge branch from Michael Terry to drop auto-upgrade-tester
    from update-manager and move it into its own source package

  [ Barry Warsaw ]
  * Begin refactoring of Computer Janitor code by renaming and
    re-situating all of it to janitor/plugincore.  This will eventually be
    removed from here into its own separate branch.
  * Merge the temporary Python 3 sprint branch back into trunk, and close
    the py3 sprint branch.
  * Moved UpdateManager/backend and UpdateManager/UnitySupport.py to the
    python*-update-manager packages for apturl.

  [ Michael Vogt ]
  * UpdateManager/GtkProgress.py:
    - fix python-apt 0.8 API crash

  [ Stéphane Graber ]
  * Drop fdsend as it's not used and doesn't build with python3.
  * Make update-manager-core a binary all packages (everything is python).
  * Split update-manager-core into python-update-manager,
    python3-update-manager and update-manager-core.
  * Build-depend and depend on python-apt >= 0.8.5~ as we need proper
    python3 support.

  [ Steve Langasek ]
  * tests/test_country_mirror.py: the test suite shouldn't fail if $LANG
    isn't set in the environment.
  * update-manager is now using python3 as an interpreter, so fix these up
    to actually be python3 packages.
 -- Colin Watson <email address hidden>   Thu, 14 Jun 2012 00:57:42 +0100