Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/dbus/connection.py", line 604, in msg_reply_handler
    reply_handler(*message.get_args_list(**get_args_opts))
  File "/usr/lib/python2.7/dist-packages/aptdaemon/client.py", line 685, in sync_properties
    self._on_property_changed(property_name, value)
  File "/usr/lib/python2.7/dist-packages/aptdaemon/client.py", line 640, in _on_property_changed
    self.emit("space-changed", value)
TypeError: could not convert type dbus.Int64 to (null) required for parameter 0