Comment 14 for bug 377476

I've just run olive-gtk and got the same error:
$ olive-gtk
/usr/lib/python2.6/dist-packages/bzrlib/plugins/gtk/ui.py:224: DeprecationWarning: bzrlib.progress.ProgressBarStack was deprecated in version 1.12.
  self._progress_bar_stack = progress.ProgressBarStack(klass=widget)
Traceback (most recent call last):
  File "/usr/bin/olive-gtk", line 92, in <module>
    from bzrlib.plugins.gtk.olive import OliveGtk
  File "/usr/lib/python2.6/dist-packages/bzrlib/plugins/gtk/olive/__init__.py", line 51, in <module>
    from bzrlib.plugins.gtk.annotate.gannotate import GAnnotateWindow
  File "/usr/lib/python2.6/dist-packages/bzrlib/plugins/gtk/annotate/gannotate.py", line 31, in <module>
    from bzrlib.plugins.gtk.revisionview import RevisionView
  File "/usr/lib/python2.6/dist-packages/bzrlib/plugins/gtk/revisionview.py", line 33, in <module>
    from bzrlib.plugins.gtk import seahorse
  File "/usr/lib/python2.6/dist-packages/bzrlib/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)
dbus.exceptions.DBusException: org.freedesktop.DBus.Error.Spawn.ChildExited: Launch helper exited with unknown return code 0

As Martin said above, running it again fixes the issue