memcached crashed after rebalance finished in Windows 7

Created an attachment (id=591)
diag of node A

Install ns server 1.6.0beta3.2b-24 on 2 Windows 7 64bit standalone machines.
Go through initial setup. Each node has 3 GB RAM and 17 GB disk.
Run memcachetest on node A
./memcachetest -h 10.2.1.55:11211 -i 50000 -c 100000 -t 16 -L 2 -v -l
During memcachetest running, add node B to node A
Rebalance cluster.
After rebalance is done, graph goes up to 16K then downs to zero.
http://screencast.com/t/MTIxNWI3OTI
I see memcached crashed in log page
http://screencast.com/t/MGVkNzU4N