Issue

• HornetQ quit responding, thread dumps show threads are stuck (in lower level components) originating from ClientProducerCreditsImpl.acquireCredits():

   java.lang.Thread.State: WAITING (parking)
    at sun.misc.Unsafe.park(Native Method)
    - parking to wait for  <0x00000000fabcac80> (a java.util.concurrent.Semaphore$NonfairSync)
    at java.util.concurrent.locks.LockSupport.park(LockSupport.java:186)
    at java.util.concurrent.locks.AbstractQueuedSynchronizer.parkAndCheckInterrupt(AbstractQueuedSynchronizer.java:834)
    at java.util.concurrent.locks.AbstractQueuedSynchronizer.doAcquireSharedInterruptibly(AbstractQueuedSynchronizer.java:994)
    at java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireSharedInterruptibly(AbstractQueuedSynchronizer.java:1303)
    at java.util.concurrent.Semaphore.acquire(Semaphore.java:472)
    at org.hornetq.core.client.impl.ClientProducerCreditsImpl.acquireCredits(ClientProducerCreditsImpl.java:90)
    at org.hornetq.core.client.impl.ClientProducerImpl.sendRegularMessage(ClientProducerImpl.java:307)
    at org.hornetq.core.client.impl.ClientProducerImpl.doSend(ClientProducerImpl.java:288)
    at org.hornetq.core.client.impl.ClientProducerImpl.send(ClientProducerImpl.java:140)
    at org.hornetq.jms.client.HornetQMessageProducer.doSend(HornetQMessageProducer.java:438)
    at org.hornetq.jms.client.HornetQMessageProducer.send(HornetQMessageProducer.java:194)