deadlock in JMS connection pool

A pool of multiple JMS connections can easily be deadlocked with moderate load.

Here is the deadlock-related thread dump subset reported by the JVM:

Found one Java-level deadlock:
=============================
"jmsTaskExecutor-2":
waiting to lock monitor 0x00ac7b34 (object 0x084e4e40, a bitronix.tm.resource.jms.JmsPooledConnection),
which is held by "jmsTaskExecutor-23"
"jmsTaskExecutor-23":
waiting to lock monitor 0x00ac7a74 (object 0x08503b68, a java.util.Collections$SynchronizedRandomAccessList),
which is held by "jmsTaskExecutor-2"

Java stack information for the threads listed above:
===================================================
"jmsTaskExecutor-2":
at bitronix.tm.resource.common.AbstractXAStatefulHolder.getState(AbstractXAStatefulHolder.java:23)

• waiting to lock <0x084e4e40> (a bitronix.tm.resource.jms.JmsPooledConnection)
  at bitronix.tm.resource.jms.JmsPooledConnection.toString(JmsPooledConnection.java:183)
• locked <0x08503b68> (a java.util.Collections$SynchronizedRandomAccessList)
  at java.lang.String.valueOf(String.java:2615)
  at java.lang.StringBuffer.append(StringBuffer.java:220)
• locked <0x2761fa18> (a java.lang.StringBuffer)
  at bitronix.tm.resource.common.XAPool.containsXAResourceHolderMatchingGtrid(XAPool.java:330)
  at bitronix.tm.resource.common.XAPool.getNotAccessible(XAPool.java:318)
  at bitronix.tm.resource.common.XAPool.getConnectionHandle(XAPool.java:96)
• locked <0x0845bd98> (a bitronix.tm.resource.common.XAPool)
  at bitronix.tm.resource.common.XAPool.getConnectionHandle(XAPool.java:68)
• locked <0x0845bd98> (a bitronix.tm.resource.common.XAPool)
  at bitronix.tm.resource.jms.PoolingConnectionFactory.createConnection(PoolingConnectionFactory.java:108)
  at org.springframework.jms.support.JmsAccessor.createConnection(JmsAccessor.java:184)
  at org.springframework.jms.listener.AbstractPollingMessageListenerContainer.access$100(AbstractPollingMessageListenerContainer.java:78)
  at org.springframework.jms.listener.AbstractPollingMessageListenerContainer$MessageListenerContainerResourceFactory.createConnection(AbstractPollingMessageListenerContainer.java:501)
  at org.springframework.jms.connection.ConnectionFactoryUtils.doGetTransactionalSession(ConnectionFactoryUtils.java:298)
  at org.springframework.jms.listener.AbstractPollingMessageListenerContainer.doReceiveAndExecute(AbstractPollingMessageListenerContainer.java:286)
  at org.springframework.jms.listener.AbstractPollingMessageListenerContainer.receiveAndExecute(AbstractPollingMessageListenerContainer.java:241)
  at org.springframework.jms.listener.DefaultMessageListenerContainer$AsyncMessageListenerInvoker.invokeListener(DefaultMessageListenerContainer.java:982)
  at org.springframework.jms.listener.DefaultMessageListenerContainer$AsyncMessageListenerInvoker.run(DefaultMessageListenerContainer.java:881)
  at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:650)
  at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:675)
  at java.lang.Thread.run(Thread.java:595)

"jmsTaskExecutor-23":
at bitronix.tm.resource.jms.JmsPooledConnection.toString(JmsPooledConnection.java:182)

• waiting to lock <0x08503b68> (a java.util.Collections$SynchronizedRandomAccessList)
  at java.lang.String.valueOf(String.java:2615)
  at java.lang.StringBuffer.append(StringBuffer.java:220)
• locked <0x275eb3f8> (a java.lang.StringBuffer)
  at bitronix.tm.resource.common.AbstractXAStatefulHolder.setState(AbstractXAStatefulHolder.java:35)
• locked <0x084e4e40> (a bitronix.tm.resource.jms.JmsPooledConnection)
  at bitronix.tm.resource.common.DeferredReleaseSynchronization.afterCompletion(DeferredReleaseSynchronization.java:33)
  at bitronix.tm.BitronixTransaction.fireAfterCompletionEvent(BitronixTransaction.java:449)
  at bitronix.tm.BitronixTransaction.commit(BitronixTransaction.java:221)
  at bitronix.tm.BitronixTransactionManager.commit(BitronixTransactionManager.java:104)
  at org.springframework.transaction.jta.JtaTransactionManager.doCommit(JtaTransactionManager.java:1028)
  at org.springframework.transaction.support.AbstractPlatformTransactionManager.processCommit(AbstractPlatformTransactionManager.java:732)
  at org.springframework.transaction.support.AbstractPlatformTransactionManager.commit(AbstractPlatformTransactionManager.java:701)
  at org.springframework.jms.listener.AbstractPollingMessageListenerContainer.receiveAndExecute(AbstractPollingMessageListenerContainer.java:255)
  at org.springframework.jms.listener.DefaultMessageListenerContainer$AsyncMessageListenerInvoker.invokeListener(DefaultMessageListenerContainer.java:982)
  at org.springframework.jms.listener.DefaultMessageListenerContainer$AsyncMessageListenerInvoker.run(DefaultMessageListenerContainer.java:881)
  at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:650)
  at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:675)
  at java.lang.Thread.run(Thread.java:595)

See http://old.nabble.com/deadlock-with-BTM-td29104439.html for the entire discussion.