Traceback (most recent call last):
  File "/usr/lib/pymodules/python2.6/dbus/connection.py", line 576, in msg_reply_handler
    reply_handler(*message.get_args_list(**get_args_opts))
  File "/usr/share/software-center/softwarecenter/backend/transactionswatcher.py", line 43, in _register_active_transactions_watch
    self.on_transactions_changed(current, queued)
  File "/usr/share/software-center/softwarecenter/backend/aptd.py", line 455, in on_transactions_changed
    error_handler=lambda x: True)
  File "/usr/lib/python2.6/dist-packages/aptdaemon/defer.py", line 510, in _deferable
    return func(*args, **kwargs)
  File "/usr/lib/python2.6/dist-packages/aptdaemon/errors.py", line 149, in _convert_dbus_exception
    return func(*args, **kwargs)
  File "/usr/lib/python2.6/dist-packages/aptdaemon/client.py", line 1023, in get_transaction
    trans.sync()
  File "/usr/lib/python2.6/dist-packages/aptdaemon/defer.py", line 510, in _deferable
    return func(*args, **kwargs)
  File "/usr/lib/python2.6/dist-packages/aptdaemon/errors.py", line 149, in _convert_dbus_exception
    return func(*args, **kwargs)
  File "/usr/lib/python2.6/dist-packages/aptdaemon/client.py", line 334, in sync
    sync_properties(properties)
  File "/usr/lib/python2.6/dist-packages/aptdaemon/client.py", line 323, in sync_properties
    self._on_property_changed(property_name, value)
  File "/usr/lib/python2.6/dist-packages/aptdaemon/client.py", line 291, in _on_property_changed
    self.emit("space-changed", value)
TypeError: could not convert type dbus.Double to (null) required for parameter 0