rebalance failed with error "badmatch,[{<17897.4408.1>,noproc}...

Monitor functional test in jenkins server, saw any rebalance test was failed
The error is

Event Module Code Server Node Time
Started rebalancing bucket default (repeated 1 times) ns_rebalancer000 ns_1@172.23.105.131 12:56:54 - Fri Aug 16, 2013
Rebalance exited with reason {{{badmatch,[

{<17897.4408.1>,noproc}]},
[{misc,sync_shutdown_many_i_am_trapping_exits, 1}, {misc,try_with_maybe_ignorant_after,2}, {gen_server,terminate,6}, {proc_lib,init_p_do_apply,3}]},
{gen_server,call,
[<0.15524.4>, {shutdown_replicator,'ns_1@172.23.105.134'},
infinity]}}
ns_orchestrator002 ns_1@172.23.105.131 12:56:27 - Fri Aug 16, 2013
<0.15514.4> exited with {{{badmatch,[{<17897.4408.1>,noproc}

]},
[

{misc,sync_shutdown_many_i_am_trapping_exits,1}

,

{misc,try_with_maybe_ignorant_after,2}

,

{gen_server,terminate,6}

,

{proc_lib,init_p_do_apply,3}

]},
{gen_server,call,
[<0.15524.4>,

{shutdown_replicator,'ns_1@172.23.105.134'}

,
infinity]}} ns_vbucket_mover000 ns_1@172.23.105.131 12:56:22 - Fri Aug 16, 2013
Bucket "default" rebalance does not seem to be swap rebalance ns_vbucket_mover000 ns_1@172.23.105.131 12:56:17 - Fri Aug 16, 2013
Bucket "default" loaded on node 'ns_1@172.23.105.132' in 0 seconds. ns_memcached001 ns_1@172.23.105.132 12:56:16 - Fri Aug 16, 2013
Bucket "default" loaded on node 'ns_1@172.23.105.133' in 0 seconds. ns_memcached001 ns_1@172.23.105.133 12:56:16 - Fri Aug 16, 2013
Bucket "default" loaded on node 'ns_1@172.23.105.134' in 0 seconds. ns_memcached001 ns_1@172.23.105.134 12:56:16 - Fri Aug 16, 2013
Deleting old data files of bucket "default" ns_storage_conf000 ns_1@172.23.105.133 12:56:16 - Fri Aug 16, 2013
Deleting old data files of bucket "default" ns_storage_conf000 ns_1@172.23.105.134 12:56:16 - Fri Aug 16, 2013
Deleting old data files of bucket "default" ns_storage_conf000 ns_1@172.23.105.132 12:56:16 - Fri Aug 16, 2013
Starting rebalance, KeepNodes = ['ns_1@172.23.105.133','ns_1@172.23.105.131',
'ns_1@172.23.105.134','ns_1@172.23.105.132'], EjectNodes = []
ns_orchestrator004 ns_1@172.23.105.131 12:56:15 - Fri Aug 16, 2013
Node ns_1@172.23.105.134 joined cluster