I enabled jpa subsystem from my applications (and from jbpm wars) then I got the error shown in this trace:
11:58:45,111 INFO [org.jboss.as.connector] (MSC service thread 1-4) JBAS010408: Starting JCA Subsystem (JBoss IronJacamar 1.0.9.Final)
11:58:45,341 INFO [org.jboss.as.naming] (MSC service thread 1-6) JBAS011802: Starting Naming Service
11:58:46,186 INFO [org.jboss.as.connector.subsystems.datasources] (ServerService Thread Pool -- 26) JBAS010404: Deploying non-JDBC-compliant driver class com.mysql.jdbc.Driver (version 5.0)
11:58:46,421 WARN [org.jboss.as.messaging] (MSC service thread 1-1) JBAS011600: AIO wasn't located on this platform, it will fall back to using pure Java NIO. If your platform is Linux, install LibAIO to enable the AIO journal
11:58:46,697 INFO [org.jboss.ws.common.management] (MSC service thread 1-4) JBWS022052: Starting JBoss Web Services - Stack CXF Server 4.1.0.Final
11:58:47,073 INFO [org.hornetq.core.server.impl.HornetQServerImpl] (MSC service thread 1-1) live server is starting with configuration HornetQ Configuration (clustered=false,backup=false,sharedStore=true,journalDirectory=C:\ApplicationServer\jboss-as-7.1.1.Final\standalone\data\messagingjournal,bindingsDirectory=C:\ApplicationServer\jboss-as-7.1.1.Final\standalone\data\messagingbindings,largeMessagesDirectory=C:\ApplicationServer\jboss-as-7.1.1.Final\standalone\data\messaginglargemessages,pagingDirectory=C:\ApplicationServer\jboss-as-7.1.1.Final\standalone\data\messagingpaging)
11:58:47,083 INFO [org.hornetq.core.server.impl.HornetQServerImpl] (MSC service thread 1-1) Waiting to obtain live lock
11:58:47,293 INFO [org.hornetq.core.persistence.impl.journal.JournalStorageManager] (MSC service thread 1-1) Using NIO Journal
11:58:47,523 INFO [org.hornetq.core.server.impl.FileLockNodeManager] (MSC service thread 1-1) Waiting to obtain live lock
11:58:47,524 INFO [org.hornetq.core.server.impl.FileLockNodeManager] (MSC service thread 1-1) Live Server Obtained live lock
11:58:48,073 INFO [org.apache.coyote.http11.Http11Protocol] (MSC service thread 1-2) Starting Coyote HTTP/1.1 on http-localhost-127.0.0.1-8080
11:58:48,226 INFO [org.jboss.as.connector.subsystems.datasources] (MSC service thread 1-4) JBAS010400: Bound data source [java:/jdbc/jbpm-ds]
11:58:48,435 INFO [org.jboss.as.server.deployment.scanner] (MSC service thread 1-8) JBAS015012: Started FileSystemDeploymentService for directory C:\ApplicationServer\jboss-as-7.1.1.Final\standalone\deployments
11:58:48,471 INFO [org.jboss.as.remoting] (MSC service thread 1-3) JBAS017100: Listening on localhost/127.0.0.1:4447
11:58:48,472 INFO [org.jboss.as.remoting] (MSC service thread 1-6) JBAS017100: Listening on /127.0.0.1:9999
11:58:50,223 INFO [org.hornetq.core.remoting.impl.netty.NettyAcceptor] (MSC service thread 1-1) Started Netty Acceptor version 3.2.5.Final-a96d88c localhost:5445 for CORE protocol
11:58:50,231 INFO [org.hornetq.core.remoting.impl.netty.NettyAcceptor] (MSC service thread 1-1) Started Netty Acceptor version 3.2.5.Final-a96d88c localhost:5455 for CORE protocol
11:58:50,234 INFO [org.hornetq.core.server.impl.HornetQServerImpl] (MSC service thread 1-1) Server is now live
11:58:50,237 INFO [org.hornetq.core.server.impl.HornetQServerImpl] (MSC service thread 1-1) HornetQ Server version 2.2.13.Final (HQ_2_2_13_FINAL_AS7, 122) [5e45cb1d-3d4b-11e2-9d07-1c7508415871]) started
11:58:50,246 INFO [org.hornetq.core.server.impl.HornetQServerImpl] (MSC service thread 1-7) trying to deploy queue jms.queue.testQ
11:58:50,264 INFO [org.jboss.as.messaging] (MSC service thread 1-7) JBAS011601: Bound messaging object to jndi name java:/queue/TestQ
11:58:50,266 INFO [org.jboss.as.messaging] (MSC service thread 1-7) JBAS011601: Bound messaging object to jndi name java:jboss/exported/jms/queue/TestQ
11:58:50,268 INFO [org.hornetq.core.server.impl.HornetQServerImpl] (MSC service thread 1-3) trying to deploy queue jms.queue.testQueue
11:58:50,271 INFO [org.jboss.as.messaging] (MSC service thread 1-3) JBAS011601: Bound messaging object to jndi name java:/queue/test
11:58:50,273 INFO [org.jboss.as.messaging] (MSC service thread 1-3) JBAS011601: Bound messaging object to jndi name java:jboss/exported/jms/queue/test
11:58:50,276 INFO [org.hornetq.core.server.impl.HornetQServerImpl] (MSC service thread 1-2) trying to deploy queue jms.topic.testTopic
11:58:50,322 INFO [org.jboss.as.messaging] (MSC service thread 1-2) JBAS011601: Bound messaging object to jndi name java:/topic/test
11:58:50,332 INFO [org.jboss.as.deployment.connector] (MSC service thread 1-3) JBAS010406: Registered connection factory java:/JmsXA
11:58:50,337 INFO [org.jboss.as.messaging] (MSC service thread 1-6) JBAS011601: Bound messaging object to jndi name java:/ConnectionFactory
11:58:50,339 INFO [org.jboss.as.messaging] (MSC service thread 1-1) JBAS011601: Bound messaging object to jndi name java:jboss/exported/jms/RemoteConnectionFactory
11:58:50,342 INFO [org.jboss.as.messaging] (MSC service thread 1-1) JBAS011601: Bound messaging object to jndi name java:/RemoteConnectionFactory
11:58:50,352 INFO [org.hornetq.ra.HornetQResourceAdapter] (MSC service thread 1-3) HornetQ resource adaptor started
11:58:50,355 INFO [org.jboss.as.connector.services.ResourceAdapterActivatorService$ResourceAdapterActivator] (MSC service thread 1-3) IJ020002: Deployed: file://RaActivatorhornetq-ra
11:58:50,360 INFO [org.jboss.as.deployment.connector] (MSC service thread 1-7) JBAS010401: Bound JCA ConnectionFactory [java:/JmsXA]
11:58:50,437 INFO [org.jboss.as.server.deployment] (MSC service thread 1-4) JBAS015876: Starting deployment of "jbpm-form-builder.war"
11:58:50,438 INFO [org.jboss.as.server.deployment] (MSC service thread 1-6) JBAS015876: Starting deployment of "jbpm-gwt-console-server.war"
11:58:50,437 INFO [org.jboss.as.server.deployment] (MSC service thread 1-7) JBAS015876: Starting deployment of "jbpm-human-task-war.war"
11:58:50,437 INFO [org.jboss.as.server.deployment] (MSC service thread 1-5) JBAS015876: Starting deployment of "drools-guvnor.war"
11:58:50,439 INFO [org.jboss.as.server.deployment] (MSC service thread 1-3) JBAS015876: Starting deployment of "jbpm-gwt-console.war"
11:58:50,438 INFO [org.jboss.as.server.deployment] (MSC service thread 1-8) JBAS015876: Starting deployment of "designer.war"
11:59:23,292 WARN [org.jboss.as.server.deployment] (MSC service thread 1-1) Class Path entry jaxb-api.jar in "/C:/ApplicationServer/jboss-as-7.1.1.Final/bin/content/jbpm-human-task-war.war/WEB-INF/lib/jaxb-impl-2.2.5.jar" does not point to a valid jar for a Class-Path reference.
11:59:23,296 WARN [org.jboss.as.server.deployment] (MSC service thread 1-1) Class Path entry activation.jar in "/C:/ApplicationServer/jboss-as-7.1.1.Final/bin/content/jbpm-human-task-war.war/WEB-INF/lib/jaxb-impl-2.2.5.jar" does not point to a valid jar for a Class-Path reference.
11:59:23,300 WARN [org.jboss.as.server.deployment] (MSC service thread 1-1) Class Path entry jsr173_1.0_api.jar in "/C:/ApplicationServer/jboss-as-7.1.1.Final/bin/content/jbpm-human-task-war.war/WEB-INF/lib/jaxb-impl-2.2.5.jar" does not point to a valid jar for a Class-Path reference.
11:59:23,303 WARN [org.jboss.as.server.deployment] (MSC service thread 1-1) Class Path entry jaxb1-impl.jar in "/C:/ApplicationServer/jboss-as-7.1.1.Final/bin/content/jbpm-human-task-war.war/WEB-INF/lib/jaxb-impl-2.2.5.jar" does not point to a valid jar for a Class-Path reference.
11:59:23,307 WARN [org.jboss.as.server.deployment] (MSC service thread 1-1) Class Path entry jaxb-api.jar in "/C:/ApplicationServer/jboss-as-7.1.1.Final/bin/content/jbpm-human-task-war.war/WEB-INF/lib/jaxb-xjc-2.2.5.jar" does not point to a valid jar for a Class-Path reference.
11:59:23,312 WARN [org.jboss.as.server.deployment] (MSC service thread 1-1) Class Path entry jaxb-impl.jar in "/C:/ApplicationServer/jboss-as-7.1.1.Final/bin/content/jbpm-human-task-war.war/WEB-INF/lib/jaxb-xjc-2.2.5.jar" does not point to a valid jar for a Class-Path reference.
11:59:23,315 WARN [org.jboss.as.server.deployment] (MSC service thread 1-1) Class Path entry jsr173_1.0_api.jar in "/C:/ApplicationServer/jboss-as-7.1.1.Final/bin/content/jbpm-human-task-war.war/WEB-INF/lib/jaxb-xjc-2.2.5.jar" does not point to a valid jar for a Class-Path reference.
11:59:23,319 WARN [org.jboss.as.server.deployment] (MSC service thread 1-1) Class Path entry activation.jar in "/C:/ApplicationServer/jboss-as-7.1.1.Final/bin/content/jbpm-human-task-war.war/WEB-INF/lib/jaxb-xjc-2.2.5.jar" does not point to a valid jar for a Class-Path reference.
11:59:23,325 WARN [org.jboss.as.server.deployment] (MSC service thread 1-1) Class Path entry activation.jar in "/C:/ApplicationServer/jboss-as-7.1.1.Final/bin/content/jbpm-human-task-war.war/WEB-INF/lib/mail-1.4.jar" does not point to a valid jar for a Class-Path reference.
11:59:27,002 WARN [org.jboss.as.server.deployment] (MSC service thread 1-1) JBAS015893: Encountered invalid class name 'org.springframework.context.ApplicationContext,org.springframework.beans.BeansException' for service type 'org.apache.cxf.bus.factory'
11:59:27,009 WARN [org.jboss.as.server.deployment] (MSC service thread 1-1) JBAS015893: Encountered invalid class name 'org.xmlpull.mxp1.MXParser,org.xmlpull.mxp1_serializer.MXSerializer' for service type 'org.xmlpull.v1.XmlPullParserFactory'
11:59:27,013 WARN [org.jboss.as.server.deployment] (MSC service thread 1-1) JBAS015893: Encountered invalid class name 'org.xmlpull.mxp1.MXParser,org.xmlpull.mxp1_serializer.MXSerializer' for service type 'org.xmlpull.v1.XmlPullParserFactory'
11:59:27,536 INFO [org.jboss.as.jpa] (MSC service thread 1-1) JBAS011401: Read persistence.xml for org.jbpm.task
11:59:28,895 WARN [org.jboss.as.dependency.private] (MSC service thread 1-5) JBAS018567: Deployment "deployment.jbpm-human-task-war.war" is using a private module ("org.jboss.netty:main") which may be changed or removed in future versions without notice.
11:59:36,246 INFO [org.jboss.as.jpa] (MSC service thread 1-5) JBAS011402: Starting Persistence Unit Service 'jbpm-human-task-war.war#org.jbpm.task'
11:59:43,583 INFO [org.hibernate.annotations.common.Version] (MSC service thread 1-5) HCANN000001: Hibernate Commons Annotations {4.0.1.Final}
11:59:43,777 INFO [org.hibernate.Version] (MSC service thread 1-5) HHH000412: Hibernate Core {4.0.1.Final}
11:59:43,907 INFO [org.hibernate.cfg.Environment] (MSC service thread 1-5) HHH000206: hibernate.properties not found
11:59:44,331 INFO [org.hibernate.cfg.Environment] (MSC service thread 1-5) HHH000021: Bytecode provider name : javassist
11:59:45,572 INFO [org.hibernate.ejb.Ejb3Configuration] (MSC service thread 1-5) HHH000204: Processing PersistenceUnitInfo [
name: org.jbpm.task
...]
11:59:47,173 ERROR [org.jboss.msc.service.fail] (MSC service thread 1-5) MSC00001: Failed to start service jboss.persistenceunit."jbpm-human-task-war.war#org.jbpm.task": org.jboss.msc.service.StartException in service jboss.persistenceunit."jbpm-human-task-war.war#org.jbpm.task": Failed to start service
at org.jboss.msc.service.ServiceControllerImpl$StartTask.run(ServiceControllerImpl.java:1767) [jboss-msc-1.0.2.GA.jar:1.0.2.GA]
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(Unknown Source) [rt.jar:1.6.0_32]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source) [rt.jar:1.6.0_32]
at java.lang.Thread.run(Unknown Source) [rt.jar:1.6.0_32]
Caused by: org.hibernate.InvalidMappingException: Unable to read XML
at org.hibernate.internal.util.xml.MappingReader.readMappingDocument(MappingReader.java:106)
at org.hibernate.ejb.Ejb3Configuration.addXMLEntities(Ejb3Configuration.java:734)
at org.hibernate.ejb.Ejb3Configuration.configure(Ejb3Configuration.java:603)
at org.hibernate.ejb.HibernatePersistence.createContainerEntityManagerFactory(HibernatePersistence.java:72)
at org.jboss.as.jpa.service.PersistenceUnitServiceImpl.createContainerEntityManagerFactory(PersistenceUnitServiceImpl.java:162)
at org.jboss.as.jpa.service.PersistenceUnitServiceImpl.start(PersistenceUnitServiceImpl.java:85)
at org.jboss.msc.service.ServiceControllerImpl$StartTask.startService(ServiceControllerImpl.java:1811) [jboss-msc-1.0.2.GA.jar:1.0.2.GA]
at org.jboss.msc.service.ServiceControllerImpl$StartTask.run(ServiceControllerImpl.java:1746) [jboss-msc-1.0.2.GA.jar:1.0.2.GA]
... 3 more
Caused by: org.dom4j.DocumentException: org.dom4j.DocumentFactory cannot be cast to org.dom4j.DocumentFactory Nested exception: org.dom4j.DocumentFactory cannot be cast to org.dom4j.DocumentFactory
at org.dom4j.io.SAXReader.read(SAXReader.java:484)
at org.hibernate.internal.util.xml.MappingReader.readMappingDocument(MappingReader.java:76)
... 10 more
11:59:58,309 INFO [org.jboss.errai.bus.server.service.bootstrap.OrderedBootstrap] (MSC service thread 1-5) Bootstrap Errai
11:59:58,322 INFO [org.jboss.errai.bus.server.service.bootstrap.DefaultComponents] (MSC service thread 1-5) using dispatcher implementation: org.jboss.errai.bus.server.AsyncDispatcher
11:59:58,691 INFO [org.jboss.errai.bus.server.WorkerFactory] (MSC service thread 1-5) initializing async worker pools (poolSize: 5; workerTimeout: 5000)
11:59:58,696 INFO [org.jboss.errai.bus.server.WorkerFactory] (MSC service thread 1-5) starting worker pool.
11:59:58,702 INFO [org.jboss.errai.bus.server.service.bootstrap.DefaultComponents] (MSC service thread 1-5) using session provider implementation: org.jboss.errai.bus.server.HttpSessionProvider
11:59:58,717 INFO [org.jboss.errai.bus.server.service.bootstrap.LoadExtensions] (MSC service thread 1-5) beging searching for Errai extensions ...
11:59:58,723 INFO [org.jboss.errai.bus.server.service.bootstrap.LoadExtensions] (MSC service thread 1-5) added extension binding: org.jboss.errai.bus.client.framework.ModelAdapter
11:59:58,726 INFO [org.jboss.errai.bus.server.service.bootstrap.LoadExtensions] (MSC service thread 1-5) total extension binding: 1
11:59:59,159 INFO [org.jboss.errai.bus.server.service.bootstrap.BootstrapContext] (MSC service thread 1-5) Running deferred bootstrap tasks ...
11:59:59,160 INFO [org.jboss.errai.bus.server.service.bootstrap.OrderedBootstrap] (MSC service thread 1-5) Bootstrap complete. Ready to rumble!
11:59:59,537 INFO [org.jboss.web] (MSC service thread 1-5) JBAS018210: Registering web context: /jbpm-console