JMS becomes unresponsive with threads waiting for MessagingPostOffice's ReaderLock

Issue

• Our JBoss messaging server becomes unresponsive.  The thread dumps show threads waiting to acquire MessagingPostOffice's ReaderLock, for example:

      "WorkerThread#18[127.0.0.1:1059]" prio=10 tid=0x000000005d766000 nid=0x1000 in Object.wait() [0x0000000048aea000]
         java.lang.Thread.State: WAITING (on object monitor)
           at java.lang.Object.wait(Native Method)
           - waiting on <0x00000000a4665e50> (a EDU.oswego.cs.dl.util.concurrent.WriterPreferenceReadWriteLock$ReaderLock)
           at java.lang.Object.wait(Object.java:485)
           at EDU.oswego.cs.dl.util.concurrent.WriterPreferenceReadWriteLock$ReaderLock.acquire(WriterPreferenceReadWriteLock.java:163)
           - locked <0x00000000a4665e50> (a EDU.oswego.cs.dl.util.concurrent.WriterPreferenceReadWriteLock$ReaderLock)
           at org.jboss.messaging.core.impl.postoffice.MessagingPostOffice.getBindingForQueueName(MessagingPostOffice.java:574)
  

  Other threads can get backed up behind these as well leading to widespread unresponsiveness.