Steps to Reproduce:1. Download latest version EAP 6.x from (tested against 6.0.1 and 6.1):
https://access.redhat.com/jbossnetwork/restricted/listSoftware.html?downloadType=distributions&product=appplatform&productChanged=yes2. Download activemq-rar-5.8.0.rar to eap6/standalone/deployments:
wget http://repo1.maven.org/maven2/org/apache/activemq/activemq-rar/5.8.0/activemq-rar-5.8.0.rar3. Build test_amp and test_amq_web using 'mvn package'4. Register activemq resource adapter in EAP 6:Edit eap6/standalone/configuration/standalone-full.xml and modify subsystem resource-adapters as:| <subsystemxmlns="urn:jboss:domain:resource-adapters:1.0">|

5. Copy test_amq/target/test_amq.jar and test_amq_web/target/test_amq_web.jar in EAP6/standalone/deployment6. Start the server:cd EAP6/bin./standalone.sh --server-config=standalone-full.xml7. Access web app to execute tests:ActiveMQ test with JMSXGroupID: http://localhost:8080/test_amq_web/testFor comparison,HornetQ test with JMSXGroupID: http://localhost:8080/test_amq_web/test28 Expected output: The messages for same JMSXGroupID should be processed sequentially by the same MDB instance pool.9 Actual Output:When invoking the test_amq_web/test we can see that messages using the same JMSXGroupID[Group-1]are not being processed sequentially by the Consume-AMQ3 MDB Pool. World 0 is processed before Hello 0 is done. In the logs we get messages in this order:| 15:00:47,031 INFO [stdout] (default-threads - 7) Consume-AMQ3 Testing MDB : Hello 0[Group-1], com.redhat.gss.test.HandleMessage@53e59730|

However when invoking test_amq_web/test2 (which uses HornetQ) we can see that the message are being processed sequentially. Hello 0 from Group-0 is done before World 0 from Group-0 is invoked.| 15:08:35,740 INFO [stdout] (Thread-1 (HornetQ-client-global-threads-1277578712)) Consume-HQ1 Testing MDB : Hello 0[Group-0], com.redhat.gss.test.HandleMessage@67092e88|

Note, you can safely ignore this warning printed by EAP on startup:| ERROR [stderr] (JMX connector) Exception in thread "JMX connector" java.lang.UnsupportedOperationException: JBAS011859: Naming context is read-only|