Traceback (most recent call last):
  File "/usr/lib/pymodules/python2.6/papyon/switchboard_manager.py", line 366, in _sb_message_received
    handler._on_message_received(message)
  File "/usr/lib/pymodules/python2.6/papyon/msnp2p/transport/switchboard.py", line 116, in _on_message_received
    self._on_chunk_received(self._peer, self._peer_guid, chunk)
  File "/usr/lib/pymodules/python2.6/papyon/msnp2p/transport/base.py", line 157, in _on_chunk_received
    self.__send_chunk(peer, peer_guid, ack_chunk)
  File "/usr/lib/pymodules/python2.6/papyon/msnp2p/transport/base.py", line 224, in __send_chunk
    self._send_chunk(peer, peer_guid, chunk)
  File "/usr/lib/pymodules/python2.6/papyon/msnp2p/transport/switchboard.py", line 98, in _send_chunk
    peer_guid + "}"}
TypeError: cannot concatenate 'str' and 'NoneType' objects