top cell error log

2014-03-11 03:20:57.565 4695 ERROR nova.cells.messaging [req-fa5271ca-0051-44b2-b0fb-da94a03ad9cb None N
one] Failed to send message to cell: Cell 'zcell2' (not_me): 'module' object has no attribute 'cast_to_s
erver'
2014-03-11 03:20:57.565 4695 TRACE nova.cells.messaging Traceback (most recent call last):
2014-03-11 03:20:57.565 4695 TRACE nova.cells.messaging   File "/usr/lib/python2.6/site-packages/nova/ce
lls/messaging.py", line 438, in process
2014-03-11 03:20:57.565 4695 TRACE nova.cells.messaging     next_hop.send_message(self)
2014-03-11 03:20:57.565 4695 TRACE nova.cells.messaging   File "/usr/lib/python2.6/site-packages/nova/ce
lls/state.py", line 110, in send_message
2014-03-11 03:20:57.565 4695 TRACE nova.cells.messaging     self.driver.send_message_to_cell(self, messa
ge)
2014-03-11 03:20:57.565 4695 TRACE nova.cells.messaging   File "/usr/lib/python2.6/site-packages/nova/ce
lls/rpc_driver.py", line 108, in send_message_to_cell
2014-03-11 03:20:57.565 4695 TRACE nova.cells.messaging     self.intercell_rpcapi.send_message_to_cell(c
ell_state, message)
2014-03-11 03:20:57.565 4695 TRACE nova.cells.messaging   File "/usr/lib/python2.6/site-packages/nova/ce
lls/rpc_driver.py", line 160, in send_message_to_cell
2014-03-11 03:20:57.565 4695 TRACE nova.cells.messaging     message=message.to_json())
2014-03-11 03:20:57.565 4695 TRACE nova.cells.messaging   File "/usr/lib/python2.6/site-packages/nova/rp
cclient.py", line 82, in cast
2014-03-11 03:20:57.565 4695 TRACE nova.cells.messaging     self._invoke(caster, ctxt, method, **kwargs)
2014-03-11 03:20:57.565 4695 TRACE nova.cells.messaging   File "/usr/lib/python2.6/site-packages/nova/rp
cclient.py", line 63, in _invoke
2014-03-11 03:20:57.565 4695 TRACE nova.cells.messaging     return cast_or_call(ctxt, msg, **self.kwargs
)
2014-03-11 03:20:57.565 4695 TRACE nova.cells.messaging   File "/usr/lib/python2.6/site-packages/nova/rp
cclient.py", line 76, in cast_to_server
2014-03-11 03:20:57.565 4695 TRACE nova.cells.messaging     ctxt, self.server_params, msg, **kwargs)
2014-03-11 03:20:57.565 4695 TRACE nova.cells.messaging   File "/usr/lib/python2.6/site-packages/nova/op
enstack/common/rpc/proxy.py", line 206, in cast_to_server
2014-03-11 03:20:57.565 4695 TRACE nova.cells.messaging     rpc.cast_to_server(context, server_params, s
elf._get_topic(topic), msg)
2014-03-11 03:20:57.565 4695 TRACE nova.cells.messaging   File "/usr/lib/python2.6/site-packages/nova/op
enstack/common/rpc/__init__.py", line 254, in cast_to_server
2014-03-11 03:20:57.565 4695 TRACE nova.cells.messaging     return _get_impl().cast_to_server(CONF, cont
ext, server_params, topic,
2014-03-11 03:20:57.565 4695 TRACE nova.cells.messaging AttributeError: 'module' object has no attribute
 'cast_to_server'
2014-03-11 03:20:57.565 4695 TRACE nova.cells.messaging
2014-03-11 03:20:57.566 4695 DEBUG nova.service [req-fa5271ca-0051-44b2-b0fb-da94a03ad9cb None None] Joi
n ServiceGroup membership for this service cells start /usr/lib/python2.6/site-packages/nova/service.py:
189