Websphere MQ resource adapter is able to read messages from queues and topics when connection didn't start.
6 tests in TCK affected:
3 for queue connection
https://jenkins.mw.lab.eng.bos.redhat.com/hudson/view/EAP5/view/IBM-MQ/job/tck5-eap5x-jdk6-jms-ibmmq/18/testReport/unknownTestSuite.0/packageTests/com.sun.ts.tests.jms.ee.all.queueconn/
3 for topic connection
https://jenkins.mw.lab.eng.bos.redhat.com/hudson/view/EAP5/view/IBM-MQ/job/tck5-eap5x-jdk6-jms-ibmmq/18/testReport/unknownTestSuite.0/packageTests/com.sun.ts.tests.jms.ee.all.topicconntests/
Impact for customers
Incorrect behaviour of connections.
Reproducer info
failed test org.jboss.as.test.ibm.mq.tck.NonStartedConnectionTestCase in
https://jenkins.mw.lab.eng.bos.redhat.com/hudson/view/EAP5/view/IBM-MQ/job/_eap5-ibm-mq-tck-failures-reproducers/
Link to reproducers execution:
https://docspace.corp.redhat.com/docs/DOC-124332#rep
Links for info how to setup IBM MQ locally
https://docspace.corp.redhat.com/docs/DOC-114804#qi
More detailed description
For example in DefaultQueue there is a message we need to receive. The code below gets message successfully, without calling Connection.start() method:

QueueConnectionFactory cf = (QueueConnectionFactory) context.lookup(JndiName);
QueueConnection newConn = cf.geQueueConnection( user, password);
QueueSession   newSess = newConn.createQueueSession(false, Session.AUTO_ACKNOWLEDGE);
Receiver   newRec = newSess.createReceiver(DefaultQueue);
TextMessage  messageReceived = (TextMessage) newRec.receiveNoWait();

Connection factories, used in test are created this way:

<connection-factories>
  <tx-connection-factory>
    <jndi-name>jms/QCF</jndi-name>
    <xa-transaction />
    <rar-name>wmq.jmsra.rar</rar-name>
    <connection-definition>javax.jms.QueueConnectionFactory</connection-definition>
    <config-property name="channel" type="java.lang.String">CH</config-property>
    <config-property name="hostName" type="java.lang.String">dev120.mw.lab.eng.bos.redhat.com</config-property>
    <config-property name="port" type="java.lang.String">1414</config-property>
    <config-property name="queueManager" type="java.lang.String">QM</config-property>
    <config-property name="transportType" type="java.lang.String">CLIENT</config-property>
    <security-domain-and-application>JmsXARealm</security-domain-and-application>
  </tx-connection-factory>
 
  <tx-connection-factory>
    <jndi-name>jms/TCF</jndi-name>
    <xa-transaction />
    <rar-name>wmq.jmsra.rar</rar-name>
    <connection-definition>javax.jms.TopicConnectionFactory</connection-definition>
    <config-property name="channel" type="java.lang.String">CH</config-property>
    <config-property name="hostName" type="java.lang.String">dev120.mw.lab.eng.bos.redhat.com</config-property>
    <config-property name="port" type="java.lang.String">1414</config-property>
    <config-property name="queueManager" type="java.lang.String">QM</config-property>
    <config-property name="transportType" type="java.lang.String">CLIENT</config-property>
    <security-domain-and-application>JmsXARealm</security-domain-and-application>
  </tx-connection-factory>
</connection-factories/>

Error message:

11-21-2012 12:43:39: SVR-TRACE: ABOUT TO INVOKE EETEST RUN METHOD!
11-21-2012 12:43:39: SVR-TRACE: Getting initial context
11-21-2012 12:43:39: SVR-TRACE: Getting QueueConnectionFactory
11-21-2012 12:43:39: SVR-TRACE: Getting Queue
11-21-2012 12:43:39: SVR-TRACE: Creating QueueConnection
11-21-2012 12:43:39: SVR-TRACE: Creating QueueSession
11-21-2012 12:43:39: SVR-TRACE: Creating receiver
11-21-2012 12:43:39: SVR-TRACE: Creating sender
11-21-2012 12:43:39: SVR-TRACE: Success - Queue Setup done
11-21-2012 12:43:39: SVR: Creating TextMessage
11-21-2012 12:43:39: SVR: Sending two TextMessages
11-21-2012 12:43:40: SVR: Receiving second message only
11-21-2012 12:43:40: SVR: Closing receiver, creating new connection without starting
11-21-2012 12:43:41: SVR: receiving first message
11-21-2012 12:43:41: SVR-ERROR: Fail: message received even though connection not started!
11-21-2012 12:43:41: SVR-ERROR: Error: failures occurred during tests
11-21-2012 12:43:41: SVR-ERROR: com.sun.ts.lib.harness.EETest$Fault: Error: failures occurred during tests
at com.sun.ts.tests.jms.ee.all.queueconn.QueueConnTests.connNotStartedQueueTest(QueueConnTests.java:199)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at com.sun.ts.lib.harness.EETest.run(EETest.java:495)
at com.sun.ts.lib.harness.ServiceEETest.run(ServiceEETest.java:112)
at com.sun.ts.tests.common.vehicle.ejb.EJBVehicle.runTest(EJBVehicle.java:70)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.jboss.invocation.Invocation.performCall(Invocation.java:386)
at org.jboss.ejb.StatefulSessionContainer$ContainerInterceptor.invoke(StatefulSessionContainer.java:620)
at org.jboss.ejb.plugins.StatefulSessionSecurityInterceptor.invoke(StatefulSessionSecurityInterceptor.java:84)
at org.jboss.ejb.plugins.SecurityInterceptor.process(SecurityInterceptor.java:233)
at org.jboss.ejb.plugins.SecurityInterceptor.invoke(SecurityInterceptor.java:211)
at org.jboss.resource.connectionmanager.CachedConnectionInterceptor.invoke(CachedConnectionInterceptor.java:156)
at org.jboss.ejb.plugins.CallValidationInterceptor.invoke(CallValidationInterceptor.java:63)
at org.jboss.ejb.plugins.AbstractTxInterceptor.invokeNext(AbstractTxInterceptor.java:121)
at org.jboss.ejb.plugins.AbstractTxInterceptorBMT.invokeNext(AbstractTxInterceptorBMT.java:173)
at org.jboss.ejb.plugins.TxInterceptorBMT.invoke(TxInterceptorBMT.java:77)
at org.jboss.ejb.plugins.StatefulSessionInstanceInterceptor.invoke(StatefulSessionInstanceInterceptor.java:348)
at org.jboss.ejb.plugins.security.PreSecurityInterceptor.process(PreSecurityInterceptor.java:100)
at org.jboss.ejb.plugins.security.PreSecurityInterceptor.invoke(PreSecurityInterceptor.java:84)
at org.jboss.ejb.plugins.LogInterceptor.invoke(LogInterceptor.java:205)
at org.jboss.ejb.plugins.ProxyFactoryFinderInterceptor.invoke(ProxyFactoryFinderInterceptor.java:138)
at org.jboss.ejb.SessionContainer.internalInvoke(SessionContainer.java:650)
at org.jboss.ejb.Container.invoke(Container.java:1092)
at sun.reflect.GeneratedMethodAccessor492.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.jboss.mx.interceptor.ReflectedDispatcher.invoke(ReflectedDispatcher.java:157)
at org.jboss.mx.server.Invocation.dispatch(Invocation.java:96)
at org.jboss.mx.server.Invocation.invoke(Invocation.java:88)
at org.jboss.mx.server.AbstractMBeanInvoker.invoke(AbstractMBeanInvoker.java:264)
at org.jboss.mx.server.MBeanServerImpl.invoke(MBeanServerImpl.java:668)
at org.jboss.invocation.unified.server.UnifiedInvoker.invoke(UnifiedInvoker.java:232)
at org.jboss.remoting.ServerInvoker.invoke(ServerInvoker.java:967)
at org.jboss.remoting.transport.socket.ServerThread.completeInvocation(ServerThread.java:791)
at org.jboss.remoting.transport.socket.ServerThread.processInvocation(ServerThread.java:744)
at org.jboss.remoting.transport.socket.ServerThread.dorun(ServerThread.java:586)
at org.jboss.remoting.transport.socket.ServerThread.run(ServerThread.java:234)