Traceback (most recent call last):
   File "/home/lis/.xchat2/xchat-notify.py", line 87, in highlight_cb
     userdata.notify()
   File "/home/lis/.xchat2/xchat-notify.py", line 75, in notify
     self.interface.Notify(self.app_name, self.replaces_id, self.app_icon, self.summary, self.body, self.actions, self.hints, self.expire_timeout)
 AttributeError: 'NoneType' object has no attribute 'Notify'