vbucketmigrator hangs after multiple rebalances with 3 nodes.

1.6.0b3c-4
centos 5.4 32bit
3 nodes

1) create a second bucket
2) add a bit of data to the server
3) add 2 nodes to the cluster and rebalance
4) remove 1 node and rebalance
5) add the node back to the cluster and rebalance
6) repeat steps 3-4

After doing a lot of rebalances eventually I would see stuck vbucketmigrator processes on each of the 3 nodes. None of them had the "-t" parameter though.