We found the bug in the application server MDB environment:

platform           solaris9 x86
Application server 8.1ee b32
mq                 FCS-6
jdk                1.4.2_05

java version "1.4.2_05"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.2_05-b04)
Java HotSpot(TM) Server VM (build 1.4.2_05-b04, mixed mode)

Code snippet and the exception stack trace are provided below.  Related java classes are attached.  

We believe that private variable "queue" in SessionQueue object cannot be null in a healthy JVM.

QA were able to reproduce this bug three times during app server MDB stress tests.  Please see "see also" for detail description for the related bugs.

<SessionImpl>
    public SessionImpl (ConnectionImpl connection, boolean isTransacted, int
           acknowledgeMode, boolean allowJMSExtension, ManagedConnection mc)
           throws JMSException {

        sessionQueue = new SessionQueue();//line #291
        sessionQueue.validateQueue(); //line #292
    }
</SessionImpl>

<SessionQueue>
    
    private MessageQueue queue = null;

    public SessionQueue() {
            queue = new PriorityQueue();
    }

    protected synchronized void validateQueue() {
        if ( queue == null ) {
            throw new java.lang.Error  //line #91 
            ("JVM Error. Message Queue is null.");
        }
    }

</SessionQueue>


The following is the stack trace when the error occurred (from bug 6177455).

==============================================================================

[#|2004-10-13T05:13:00.740+0530|INFO|sun-appserver-ee8.1|javax.enterprise.system.container.ejb.mdb|_ThreadID=43;|MDB00037: [XATStress:XAT
StressMDB2]: Message-driven bean invocation exception: [javax.ejb.EJBException]|#]

[#|2004-10-13T05:13:00.741+0530|INFO|sun-appserver-ee8.1|javax.enterprise.system.container.ejb.mdb|_ThreadID=43;|javax.ejb.EJBException
javax.ejb.EJBException
        at com.sun.ejb.containers.BaseContainer.processSystemException(BaseContainer.java:2800)
        at com.sun.ejb.containers.BaseContainer.completeNewTx(BaseContainer.java:2706)
        at com.sun.ejb.containers.BaseContainer.postInvokeTx(BaseContainer.java:2514)
        at com.sun.ejb.containers.MessageBeanContainer.afterMessageDeliveryInternal(MessageBeanContainer.java:1071)
        at com.sun.ejb.containers.MessageBeanContainer.afterMessageDelivery(MessageBeanContainer.java:1042)
        at com.sun.ejb.containers.MessageBeanListenerImpl.afterMessageDelivery(MessageBeanListenerImpl.java:46)
        at com.sun.enterprise.connectors.inflow.MessageEndpointInvocationHandler.invoke(MessageEndpointInvocationHandler.java:105)
        at $Proxy17.afterDelivery(Unknown Source)
        at com.sun.messaging.jms.ra.OnMessageRunner.run(OnMessageRunner.java:228)
        at com.sun.enterprise.connectors.work.OneWork.doWork(OneWork.java:45)
        at com.sun.corba.ee.impl.orbutil.threadpool.ThreadPoolImpl$WorkerThread.run(ThreadPoolImpl.java:398)
Caused by: java.lang.Error: JVM Error. Message Queue is null. Create time: 1097624580268 duration: 0
        at com.sun.messaging.jmq.jmsclient.SessionQueue.validateQueue(SessionQueue.java:91)
        at com.sun.messaging.jmq.jmsclient.SessionImpl.<init>(SessionImpl.java:292)
        at com.sun.messaging.jmq.jmsclient.SessionImpl.<init>(SessionImpl.java:271)
        at com.sun.messaging.jmq.jmsclient.UnifiedSessionImpl.<init>(UnifiedSessionImpl.java:45)
        at com.sun.messaging.jmq.jmsclient.XASessionImpl.<init>(XASessionImpl.java:65)
        at com.sun.messaging.jmq.jmsclient.XATopicSessionImpl.<init>(XATopicSessionImpl.java:61)
        at com.sun.messaging.jmq.jmsclient.XAConnectionImpl.createTopicSession(XAConnectionImpl.java:154)
        at com.sun.messaging.jms.ra.ConnectionAdapter.createTopicSession(ConnectionAdapter.java:398)
        at XATStressMDB2.onMessage(XATStressMDB2.java:166)
        at sun.reflect.GeneratedMethodAccessor87.invoke(Unknown Source)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:324)
        at com.sun.enterprise.security.SecurityUtil$2.run(SecurityUtil.java:149)
        at java.security.AccessController.doPrivileged(Native Method)
        at com.sun.enterprise.security.application.EJBSecurityManager.doAsPrivileged(EJBSecurityManager.java:950)
        at com.sun.enterprise.security.SecurityUtil.invoke(SecurityUtil.java:154)
        at com.sun.ejb.containers.MessageBeanContainer.deliverMessage(MessageBeanContainer.java:956)
        at com.sun.ejb.containers.MessageBeanListenerImpl.deliverMessage(MessageBeanListenerImpl.java:42)
        at com.sun.enterprise.connectors.inflow.MessageEndpointInvocationHandler.invoke(MessageEndpointInvocationHandler.java:130)
        at $Proxy17.onMessage(Unknown Source)
        at com.sun.messaging.jms.ra.OnMessageRunner.run(OnMessageRunner.java:173)
        ... 2 more
-----------------------------------------------------------------------
###@###.### 10/14/04 19:58 GMT


Correction:  The VM option used was client VM, not server VM:

java version "1.4.2_05"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.2_05-b04)
Java HotSpot(TM) Client VM (build 1.4.2_05-b04, mixed mode)
###@###.### 10/19/04 05:46 GMT