Failover of topic with durable consumer causes NPE sometimes

I'm sending messages to a topic with 1 durable client. While sending messages I'm disconnecting and reconnecting the durable client and killing master broker. The exception is thrown just occasionally.

Here is the log with exception:

— Producing to masterslave-failover#1418736576204
Produced: Msg#0
— Stopping: broker2
Produced: Msg#500
— Durable consumer disconnected
Produced: Msg#1000
— Starting: broker2
— Stopping: broker1
Produced: Msg#1500
Produced: Msg#2000
— Starting: broker1
— Stopping: broker2
Produced: Msg#2500
— Durable consumer reconnected
— Starting: broker2
— Stopping: broker1
Produced: Msg#3000
Produced: Msg#3500
Produced: Msg#4000
— Starting: broker1
— Stopping: broker2
Produced: Msg#4500
Produced: Msg#5000
— Starting: broker2
— Stopping: broker1
Produced: Msg#5500
Produced: Msg#6000
Produced: Msg#6500
— Starting: broker1
— Stopping: broker2
Produced: Msg#7000
Produced: Msg#7500
— Starting: broker2
— Stopping: broker1
Produced: Msg#8000
Produced: Msg#8500
— Starting: broker1
— Stopping: broker2
Produced: Msg#9000
Produced: Msg#9500
— Starting: broker2
— Stopping: broker1
javax.jms.JMSException: java.lang.NullPointerException
at org.apache.activemq.util.JMSExceptionSupport.create(JMSExceptionSupport.java:54)
at org.apache.activemq.ActiveMQConnection.syncSendPacket(ActiveMQConnection.java:1417)
at org.apache.activemq.ActiveMQConnection.syncSendPacket(ActiveMQConnection.java:1345)
at org.apache.activemq.ActiveMQSession.send(ActiveMQSession.java:1904)
at org.apache.activemq.ActiveMQMessageProducer.send(ActiveMQMessageProducer.java:288)
at org.apache.activemq.ActiveMQMessageProducer.send(ActiveMQMessageProducer.java:223)
at org.apache.activemq.ActiveMQMessageProducerSupport.send(ActiveMQMessageProducerSupport.java:241)
at org.jboss.fuse.qa.amq.failover.client.KillingClient.doProduce(KillingClient.java:106)
at org.jboss.fuse.qa.amq.failover.client.KillingClient.startNonTransactedProducing(KillingClient.java:56)
at org.jboss.fuse.qa.amq.failover.client.KTopicClient.startNonTransactedProducing(KTopicClient.java:54)
at org.jboss.fuse.qa.amq.failover.MasterSlaveFailoverTest.shouldGetAllMessagesFromDurableTopic(MasterSlaveFailoverTest.java:74)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:47)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:44)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)
at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:27)
at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:271)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:70)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:50)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:238)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:63)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:236)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:53)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:229)
at org.junit.runners.ParentRunner.run(ParentRunner.java:309)
at org.apache.maven.surefire.junit4.JUnit4Provider.execute(JUnit4Provider.java:264)
at org.apache.maven.surefire.junit4.JUnit4Provider.executeTestSet(JUnit4Provider.java:153)
at org.apache.maven.surefire.junit4.JUnit4Provider.invoke(JUnit4Provider.java:124)
at org.apache.maven.surefire.booter.ForkedBooter.invokeProviderInSameClassLoader(ForkedBooter.java:200)
at org.apache.maven.surefire.booter.ForkedBooter.runSuitesInProcess(ForkedBooter.java:153)
at org.apache.maven.surefire.booter.ForkedBooter.main(ForkedBooter.java:103)
Caused by: java.lang.NullPointerException
at org.apache.activemq.broker.region.cursors.AbstractStoreCursor.setLastCachedId(AbstractStoreCursor.java:272)
at org.apache.activemq.broker.region.cursors.AbstractStoreCursor.addMessageLast(AbstractStoreCursor.java:205)
at org.apache.activemq.broker.region.cursors.StoreDurableSubscriberCursor.addMessageLast(StoreDurableSubscriberCursor.java:198)
at org.apache.activemq.broker.region.PrefetchSubscription.add(PrefetchSubscription.java:159)
at org.apache.activemq.broker.region.DurableTopicSubscription.add(DurableTopicSubscription.java:272)
at org.apache.activemq.broker.region.policy.SimpleDispatchPolicy.dispatch(SimpleDispatchPolicy.java:48)
at org.apache.activemq.broker.region.Topic.dispatch(Topic.java:717)
at org.apache.activemq.broker.region.Topic.doMessageSend(Topic.java:510)
at org.apache.activemq.broker.region.Topic.send(Topic.java:441)
at org.apache.activemq.broker.region.AbstractRegion.send(AbstractRegion.java:419)
at org.apache.activemq.broker.region.RegionBroker.send(RegionBroker.java:462)
at org.apache.activemq.broker.jmx.ManagedRegionBroker.send(ManagedRegionBroker.java:297)
at org.apache.activemq.broker.BrokerFilter.send(BrokerFilter.java:152)
at org.apache.activemq.broker.CompositeDestinationBroker.send(CompositeDestinationBroker.java:96)
at org.apache.activemq.broker.TransactionBroker.send(TransactionBroker.java:307)
at org.apache.activemq.broker.BrokerFilter.send(BrokerFilter.java:152)
at org.apache.activemq.broker.MutableBrokerFilter.send(MutableBrokerFilter.java:157)
at org.apache.activemq.broker.TransportConnection.processMessage(TransportConnection.java:541)
at org.apache.activemq.command.ActiveMQMessage.visit(ActiveMQMessage.java:768)
at org.apache.activemq.broker.TransportConnection.service(TransportConnection.java:334)
at org.apache.activemq.broker.TransportConnection$1.onCommand(TransportConnection.java:188)
at org.apache.activemq.transport.MutexTransport.onCommand(MutexTransport.java:50)
at org.apache.activemq.transport.WireFormatNegotiator.onCommand(WireFormatNegotiator.java:113)
at org.apache.activemq.transport.AbstractInactivityMonitor.onCommand(AbstractInactivityMonitor.java:270)
at org.apache.activemq.transport.TransportSupport.doConsume(TransportSupport.java:83)
at org.apache.activemq.transport.tcp.TcpTransport.doRun(TcpTransport.java:214)
at org.apache.activemq.transport.tcp.TcpTransport.run(TcpTransport.java:196)
at java.lang.Thread.run(Thread.java:745)