NPE at transaction rollback (again)

2011-07-20 05:54:39,659 WARN  [arjuna] (Transaction Reaper Worker 0) ARJUNA12091: Top-level abort of action 0:ffff0aca9676:8727:4e26a548:2ce received TwoPhaseOutcome.FINISH_ERROR from com.arjuna.ats.arjuna.coordinator.AbstractRecord
2011-07-20 05:54:39,659 WARN  [arjuna] (Transaction Reaper Worker 0) ARJUNA12121: TransactionReaper::doCancellations worker Thread[Transaction Reaper Worker 0,5,main] successfully canceled TX 0:ffff0aca9676:8727:4e26a548:2ce
2011-07-20 05:54:39,659 WARN  [jta] (Transaction Reaper Worker 0) ARJUNA16045: attempted rollback of < formatId=131076, gtrid_length=29, bqual_length=28, tx_uid=0:ffff0aca9676:8727:4e26a548:2d2, node_name=1, branch_uid=0:ffff0aca9676:8727:4e26a548:2d3, eis_name=unknown eis name > (TransactionXaAdapter{localTransaction=LocalXaTransaction{xid=< formatId=131076, gtrid_length=29, bqual_length=28, tx_uid=0:ffff0aca9676:8727:4e26a548:2d2, node_name=1, branch_uid=0:ffff0aca9676:8727:4e26a548:2d3, eis_name=unknown eis name >} LocalTransaction{remoteLockedNodes=[MainOwnerChangedTest-NodeA-55288], isMarkedForRollback=false, transaction=TransactionImple < ac, BasicAction: 0:ffff0aca9676:8727:4e26a548:2d2 status: ActionStatus.ABORTING >} org.infinispan.transaction.xa.LocalXaTransaction@8b0c6a04}) failed with exception code -
java.lang.NullPointerException
	at java.util.concurrent.ConcurrentHashMap.get(ConcurrentHashMap.java:768)
	at org.infinispan.transaction.TransactionTable.failureCompletingTransaction(TransactionTable.java:195)
	at org.infinispan.transaction.TransactionCoordinator.rollback(TransactionCoordinator.java:159)
	at org.infinispan.transaction.xa.TransactionXaAdapter.rollback(TransactionXaAdapter.java:135)
	at com.arjuna.ats.internal.jta.resources.arjunacore.XAResourceRecord.topLevelAbort(XAResourceRecord.java:337)
	at com.arjuna.ats.arjuna.coordinator.BasicAction.doAbort(BasicAction.java:2869)
	at com.arjuna.ats.arjuna.coordinator.BasicAction.doAbort(BasicAction.java:2848)
	at com.arjuna.ats.arjuna.coordinator.BasicAction.Abort(BasicAction.java:1613)
	at com.arjuna.ats.arjuna.coordinator.TwoPhaseCoordinator.cancel(TwoPhaseCoordinator.java:119)
	at com.arjuna.ats.arjuna.AtomicAction.cancel(AtomicAction.java:212)
	at com.arjuna.ats.arjuna.coordinator.TransactionReaper.doCancellations(TransactionReaper.java:367)
	at com.arjuna.ats.internal.arjuna.coordinator.ReaperWorkerThread.run(ReaperWorkerThread.java:79)