this is what happens for "bzr selftest":

beuno@dell-desktop:~$ bzr selftest
testing: /usr/bin/bzr
   /usr/lib/python2.6/dist-packages/bzrlib (1.13dev python2.6.1)

/usr/lib/python2.6/dist-packages/Crypto/Hash/SHA.py:6: DeprecationWarning: the sha module is deprecated; use the hashlib module instead
  from sha import *
/usr/lib/python2.6/dist-packages/Crypto/Hash/MD5.py:6: DeprecationWarning: the md5 module is deprecated; use hashlib instead
  from md5 import *
bzr: ERROR: dbus.exceptions.DBusException: org.freedesktop.DBus.Error.Spawn.ChildExited: Launch helper exited with unknown return code 0

Traceback (most recent call last):
  File "/usr/lib/python2.6/dist-packages/bzrlib/commands.py", line 921, in run_bzr_catch_errors
    return run_bzr(argv)
  File "/usr/lib/python2.6/dist-packages/bzrlib/commands.py", line 866, in run_bzr
    ret = run(*run_argv)
  File "/usr/lib/python2.6/dist-packages/bzrlib/commands.py", line 547, in run_argv_aliases
    return self.run(**all_cmd_args)
  File "/usr/lib/python2.6/dist-packages/bzrlib/builtins.py", line 3205, in run
    result = selftest(**selftest_kwargs)
  File "/usr/lib/python2.6/dist-packages/bzrlib/tests/__init__.py", line 2703, in selftest
    suite = test_suite(keep_only, starting_with)
  File "/usr/lib/python2.6/dist-packages/bzrlib/tests/__init__.py", line 3122, in test_suite
    plugin_suite = plugin.test_suite()
  File "/usr/lib/python2.6/dist-packages/bzrlib/plugin.py", line 453, in test_suite
    return self.module.test_suite()
  File "/home/beuno/.bazaar/plugins/gtk/__init__.py", line 657, in test_suite
    result.addTest(tests.test_suite())
  File "/home/beuno/.bazaar/plugins/gtk/tests/__init__.py", line 36, in test_suite
    result.addTest(loader.loadTestsFromModuleNames(["%s.%s" % (__name__, i) for i in testmod_names]))
  File "/usr/lib/python2.6/dist-packages/bzrlib/tests/TestUtil.py", line 92, in loadTestsFromModuleNames
    result.addTests(self.loadTestsFromModuleName(name))
  File "/usr/lib/python2.6/dist-packages/bzrlib/tests/TestUtil.py", line 97, in loadTestsFromModuleName
    module = _load_module_by_name(name)
  File "/usr/lib/python2.6/dist-packages/bzrlib/tests/TestUtil.py", line 166, in _load_module_by_name
    module = __import__(mod_name)
  File "/home/beuno/.bazaar/plugins/gtk/tests/test_preferences.py", line 18, in <module>
    from bzrlib.plugins.gtk.olive import Preferences
  File "/home/beuno/.bazaar/plugins/gtk/olive/__init__.py", line 51, in <module>
    from bzrlib.plugins.gtk.annotate.gannotate import GAnnotateWindow
  File "/home/beuno/.bazaar/plugins/gtk/annotate/gannotate.py", line 31, in <module>
    from bzrlib.plugins.gtk.revisionview import RevisionView
  File "/home/beuno/.bazaar/plugins/gtk/revisionview.py", line 33, in <module>
    from bzrlib.plugins.gtk import seahorse
  File "/home/beuno/.bazaar/plugins/gtk/seahorse.py", line 33, in <module>
    crypto = dbus.Interface(bus.get_object(BUS_NAME, CRYPTO_PATH),
  File "/var/lib/python-support/python2.6/dbus/bus.py", line 244, in get_object
    follow_name_owner_changes=follow_name_owner_changes)
  File "/var/lib/python-support/python2.6/dbus/proxies.py", line 241, in __init__
    self._named_service = conn.activate_name_owner(bus_name)
  File "/var/lib/python-support/python2.6/dbus/bus.py", line 183, in activate_name_owner
    self.start_service_by_name(bus_name)
  File "/var/lib/python-support/python2.6/dbus/bus.py", line 281, in start_service_by_name
    'su', (bus_name, flags)))
  File "/var/lib/python-support/python2.6/dbus/connection.py", line 622, in call_blocking
    message, timeout)
DBusException: org.freedesktop.DBus.Error.Spawn.ChildExited: Launch helper exited with unknown return code 0