Erro: JSF 2.0 com Jboss as 7.1

Boa tarde

Pessoal estou usando jboss as 7.1, jsf 2.0 e hibernate 4;

Na hora de persistir recebo o seguinte erro:

12:27:54,519 WARNING [javax.enterprise.resource.webcontainer.jsf.lifecycle] (http-localhost-127.0.0.1-8080-1) #{contaBean.grava}: java.lang.NullPointerException: javax.faces.FacesException: #{contaBean.grava}: java.lang.NullPointerException
	at com.sun.faces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:118) [jsf-impl-2.1.7-jbossorg-2.jar:]
	at javax.faces.component.UICommand.broadcast(UICommand.java:315) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
	at javax.faces.component.UIViewRoot.broadcastEvents(UIViewRoot.java:794) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
	at javax.faces.component.UIViewRoot.processApplication(UIViewRoot.java:1259) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
	at com.sun.faces.lifecycle.InvokeApplicationPhase.execute(InvokeApplicationPhase.java:81) [jsf-impl-2.1.7-jbossorg-2.jar:]
	at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101) [jsf-impl-2.1.7-jbossorg-2.jar:]
	at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:118) [jsf-impl-2.1.7-jbossorg-2.jar:]
	at javax.faces.webapp.FacesServlet.service(FacesServlet.java:593) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:329) [jbossweb-7.0.13.Final.jar:]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:248) [jbossweb-7.0.13.Final.jar:]
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:275) [jbossweb-7.0.13.Final.jar:]
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:161) [jbossweb-7.0.13.Final.jar:]
	at org.jboss.as.jpa.interceptor.WebNonTxEmCloserValve.invoke(WebNonTxEmCloserValve.java:50) [jboss-as-jpa-7.1.1.Final.jar:7.1.1.Final]
	at org.jboss.as.web.security.SecurityContextAssociationValve.invoke(SecurityContextAssociationValve.java:153) [jboss-as-web-7.1.1.Final.jar:7.1.1.Final]
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:155) [jbossweb-7.0.13.Final.jar:]
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102) [jbossweb-7.0.13.Final.jar:]
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) [jbossweb-7.0.13.Final.jar:]
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:368) [jbossweb-7.0.13.Final.jar:]
	at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:877) [jbossweb-7.0.13.Final.jar:]
	at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:671) [jbossweb-7.0.13.Final.jar:]
	at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:930) [jbossweb-7.0.13.Final.jar:]
	at java.lang.Thread.run(Thread.java:722) [rt.jar:1.7.0_15]
Caused by: javax.faces.el.EvaluationException: java.lang.NullPointerException
	at javax.faces.component.MethodBindingMethodExpressionAdapter.invoke(MethodBindingMethodExpressionAdapter.java:102) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
	at com.sun.faces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:102) [jsf-impl-2.1.7-jbossorg-2.jar:]
	... 21 more
Caused by: java.lang.NullPointerException
	at org.hibernate.engine.transaction.internal.jta.JtaStatusHelper.getStatus(JtaStatusHelper.java:73) [hibernate-core-4.0.1.Final.jar:4.0.1.Final]
	at org.hibernate.engine.transaction.internal.jta.JtaStatusHelper.isActive(JtaStatusHelper.java:115) [hibernate-core-4.0.1.Final.jar:4.0.1.Final]
	at org.hibernate.engine.transaction.internal.jta.CMTTransaction.join(CMTTransaction.java:149) [hibernate-core-4.0.1.Final.jar:4.0.1.Final]
	at org.hibernate.ejb.AbstractEntityManagerImpl.joinTransaction(AbstractEntityManagerImpl.java:1207) [hibernate-entitymanager-4.0.1.Final.jar:4.0.1.Final]
	at org.hibernate.ejb.AbstractEntityManagerImpl.postInit(AbstractEntityManagerImpl.java:176) [hibernate-entitymanager-4.0.1.Final.jar:4.0.1.Final]
	at org.hibernate.ejb.EntityManagerImpl.<init>(EntityManagerImpl.java:89) [hibernate-entitymanager-4.0.1.Final.jar:4.0.1.Final]
	at org.hibernate.ejb.EntityManagerFactoryImpl.createEntityManager(EntityManagerFactoryImpl.java:125) [hibernate-entitymanager-4.0.1.Final.jar:4.0.1.Final]
	at org.hibernate.ejb.EntityManagerFactoryImpl.createEntityManager(EntityManagerFactoryImpl.java:120) [hibernate-entitymanager-4.0.1.Final.jar:4.0.1.Final]
	at br.com.caelum.financas.infra.JPAUtil.getEntityManager(JPAUtil.java:12) [classes:]
	at br.com.caelum.financas.mb.ContaBean.grava(ContaBean.java:24) [classes:]
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) [rt.jar:1.7.0_15]
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) [rt.jar:1.7.0_15]
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) [rt.jar:1.7.0_15]
	at java.lang.reflect.Method.invoke(Method.java:601) [rt.jar:1.7.0_15]
	at org.apache.el.parser.AstValue.invoke(AstValue.java:262) [jbossweb-7.0.13.Final.jar:]
	at org.apache.el.MethodExpressionImpl.invoke(MethodExpressionImpl.java:278) [jbossweb-7.0.13.Final.jar:]
	at com.sun.faces.facelets.el.TagMethodExpression.invoke(TagMethodExpression.java:105) [jsf-impl-2.1.7-jbossorg-2.jar:]
	at javax.faces.component.MethodBindingMethodExpressionAdapter.invoke(MethodBindingMethodExpressionAdapter.java:88) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
	... 22 more

12:27:54,680 ERROR [org.apache.catalina.core.ContainerBase.[jboss.web].[default-host].[/jbossashibernate4].[Faces Servlet]] (http-localhost-127.0.0.1-8080-1) Servlet.service() for servlet Faces Servlet threw exception: java.lang.NullPointerException
	at org.hibernate.engine.transaction.internal.jta.JtaStatusHelper.getStatus(JtaStatusHelper.java:73) [hibernate-core-4.0.1.Final.jar:4.0.1.Final]
	at org.hibernate.engine.transaction.internal.jta.JtaStatusHelper.isActive(JtaStatusHelper.java:115) [hibernate-core-4.0.1.Final.jar:4.0.1.Final]
	at org.hibernate.engine.transaction.internal.jta.CMTTransaction.join(CMTTransaction.java:149) [hibernate-core-4.0.1.Final.jar:4.0.1.Final]
	at org.hibernate.ejb.AbstractEntityManagerImpl.joinTransaction(AbstractEntityManagerImpl.java:1207) [hibernate-entitymanager-4.0.1.Final.jar:4.0.1.Final]
	at org.hibernate.ejb.AbstractEntityManagerImpl.postInit(AbstractEntityManagerImpl.java:176) [hibernate-entitymanager-4.0.1.Final.jar:4.0.1.Final]
	at org.hibernate.ejb.EntityManagerImpl.<init>(EntityManagerImpl.java:89) [hibernate-entitymanager-4.0.1.Final.jar:4.0.1.Final]
	at org.hibernate.ejb.EntityManagerFactoryImpl.createEntityManager(EntityManagerFactoryImpl.java:125) [hibernate-entitymanager-4.0.1.Final.jar:4.0.1.Final]
	at org.hibernate.ejb.EntityManagerFactoryImpl.createEntityManager(EntityManagerFactoryImpl.java:120) [hibernate-entitymanager-4.0.1.Final.jar:4.0.1.Final]
	at br.com.caelum.financas.infra.JPAUtil.getEntityManager(JPAUtil.java:12) [classes:]
	at br.com.caelum.financas.mb.ContaBean.grava(ContaBean.java:24) [classes:]
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) [rt.jar:1.7.0_15]
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57) [rt.jar:1.7.0_15]
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) [rt.jar:1.7.0_15]
	at java.lang.reflect.Method.invoke(Method.java:601) [rt.jar:1.7.0_15]
	at org.apache.el.parser.AstValue.invoke(AstValue.java:262) [jbossweb-7.0.13.Final.jar:]
	at org.apache.el.MethodExpressionImpl.invoke(MethodExpressionImpl.java:278) [jbossweb-7.0.13.Final.jar:]
	at com.sun.faces.facelets.el.TagMethodExpression.invoke(TagMethodExpression.java:105) [jsf-impl-2.1.7-jbossorg-2.jar:]
	at javax.faces.component.MethodBindingMethodExpressionAdapter.invoke(MethodBindingMethodExpressionAdapter.java:88) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
	at com.sun.faces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:102) [jsf-impl-2.1.7-jbossorg-2.jar:]
	at javax.faces.component.UICommand.broadcast(UICommand.java:315) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
	at javax.faces.component.UIViewRoot.broadcastEvents(UIViewRoot.java:794) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
	at javax.faces.component.UIViewRoot.processApplication(UIViewRoot.java:1259) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
	at com.sun.faces.lifecycle.InvokeApplicationPhase.execute(InvokeApplicationPhase.java:81) [jsf-impl-2.1.7-jbossorg-2.jar:]
	at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101) [jsf-impl-2.1.7-jbossorg-2.jar:]
	at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:118) [jsf-impl-2.1.7-jbossorg-2.jar:]
	at javax.faces.webapp.FacesServlet.service(FacesServlet.java:593) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:329) [jbossweb-7.0.13.Final.jar:]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:248) [jbossweb-7.0.13.Final.jar:]
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:275) [jbossweb-7.0.13.Final.jar:]
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:161) [jbossweb-7.0.13.Final.jar:]
	at org.jboss.as.jpa.interceptor.WebNonTxEmCloserValve.invoke(WebNonTxEmCloserValve.java:50) [jboss-as-jpa-7.1.1.Final.jar:7.1.1.Final]
	at org.jboss.as.web.security.SecurityContextAssociationValve.invoke(SecurityContextAssociationValve.java:153) [jboss-as-web-7.1.1.Final.jar:7.1.1.Final]
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:155) [jbossweb-7.0.13.Final.jar:]
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102) [jbossweb-7.0.13.Final.jar:]
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) [jbossweb-7.0.13.Final.jar:]
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:368) [jbossweb-7.0.13.Final.jar:]
	at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:877) [jbossweb-7.0.13.Final.jar:]
	at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:671) [jbossweb-7.0.13.Final.jar:]
	at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:930) [jbossweb-7.0.13.Final.jar:]
	at java.lang.Thread.run(Thread.java:722) [rt.jar:1.7.0_15]

acredito ser ser alguma coisa com jsf-impl-2.1.7-jbossorg-2.jar

alguem ja passo por isso , sabe resolver ?

Boa noite galera

apos muita pesquisa, solucionei o problema.

Pra quem tiver passando a mesma dificuldade, declarei o seguinte no persistence.xml:

<persistence-unit name="xmlPersis" transaction-type="RESOURCE_LOCAL">

http://www.guj.com.br/java/256271-resolvidonullpointer-ao-tentar-criar-um-entitymanager-jboss-as-7--jpa-20--hibernate-4