can someone explain me why my activeMQ client is stalled in such situation (i have 10 threads blocked like this having as consequence a complete blocking of my client application):

"http-8081-Processor6" daemon prio=10 tid=00841c38 nid=512 lwp_id=2426611 waiting on condition [236f3000..236f153c]
   java.lang.Thread.State: WAITING (parking)
        at sun.misc.Unsafe.park(Native Method)
        - parking to wait for  <40ae1828> (a java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject)
        at java.util.concurrent.locks.LockSupport.park(LockSupport.java:158)
        at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:1889)
        at java.util.concurrent.ArrayBlockingQueue.take(ArrayBlockingQueue.java:317)
        at org.apache.activemq.transport.FutureResponse.getResult(FutureResponse.java:40)
        at org.apache.activemq.transport.ResponseCorrelator.request(ResponseCorrelator.java:80)
        at org.apache.activemq.ActiveMQConnection.syncSendPacket(ActiveMQConnection.java:1233)
        at org.apache.activemq.ActiveMQSession.send(ActiveMQSession.java:1659)
        - locked <40ae01e8> (a java.lang.Object)
        at org.apache.activemq.ActiveMQMessageProducer.send(ActiveMQMessageProducer.java:227)
        at org.apache.activemq.ActiveMQMessageProducerSupport.send(ActiveMQMessageProducerSupport.java:241)
        at be.rmi.shark.JMSEventManager.sendEvent(JMSEventManager.java:146)

considering that the activeMQ lists size, as referenced by activeMQ admin interface are as follow:
Name   Number Of Pending Messages   Number Of Consumers   Messages Sent   Messages Received   Views   Operations  
WF.Regraph 0 1 1714 1720 Browse Send To Purge Delete
WF.Notify 0 1 1696 1742 Browse Send To Purge Delete
WF.IncomingEvents 0 0 0 0 Browse Send To Purge Delete

Is this to be considered normal that i must restart activeMQ producers on a regular basis because of those this stalling? Where can i find clear documentation on proper configuration of activeMQ to prevent this stalling? Thank you.

David Delbecq
Institut Royal Météorologique