NPE in org.gatein.cdi.contexts.PortletRedisplayedContextImpl

Issue

Our JBoss Portal server provides some remote JSF portlets accessed using WSRP v2. We have the issue that sometimes a NullPointerException occurs in class org.gatein.cdi.contexts.PortletRedisplayedContextImpl:

10:49:54,856 ERROR [org.apache.catalina.core.ContainerBase.[jboss.web].[default-host].[/cdi-scopes-portlet]] (http-/127.0.0.1:8080-2) JBWEB000233: Exception sending request initialized lifecycle event to listener instance of class org.gatein.cdi.contexts.listeners.CDIServletListener: java.lang.NullPointerException
    at org.gatein.cdi.contexts.PortletRedisplayedContextImpl.transition(PortletRedisplayedContextImpl.java:108) [gatein-cdi-contexts-3.8.16.Final-redhat-1.jar:3.8.16.Final-redhat-1]
    at org.gatein.cdi.contexts.listeners.AbstractCDIServletListener.requestInitialized(AbstractCDIServletListener.java:53) [gatein-cdi-contexts-3.8.16.Final-redhat-1.jar:3.8.16.Final-redhat-1]
    at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:775) [jbossweb-7.5.7.Final-redhat-1.jar:7.5.7.Final-redhat-1]
    at org.apache.catalina.core.ApplicationDispatcher.doInclude(ApplicationDispatcher.java:718) [jbossweb-7.5.7.Final-redhat-1.jar:7.5.7.Final-redhat-1]
    at org.apache.catalina.core.ApplicationDispatcher.include(ApplicationDispatcher.java:655) [jbossweb-7.5.7.Final-redhat-1.jar:7.5.7.Final-redhat-1]
    at org.gatein.wci.command.CommandServlet.include(CommandServlet.java:84) [wci-wci-2.4.2.Final-redhat-1.jar:2.4.2.Final-redhat-1]
    at org.gatein.wci.command.CommandDispatcher.include(CommandDispatcher.java:58) [wci-wci-2.4.2.Final-redhat-1.jar:2.4.2.Final-redhat-1]
    at org.gatein.wci.jboss.JB7ServletContainerContext.include(JB7ServletContainerContext.java:110) [wci-jboss7-2.4.2.Final-redhat-1.jar:2.4.2.Final-redhat-1]
    at org.gatein.wci.ServletContainer.include(ServletContainer.java:395) [wci-wci-2.4.2.Final-redhat-1.jar:2.4.2.Final-redhat-1]
    at org.exoplatform.portal.webui.application.ExoServerContext.dispatch(ExoServerContext.java:45) [exo.portal.webui.portal-3.8.16.Final-redhat-1.jar:3.8.16.Final-redhat-1]
    at org.gatein.pc.portlet.aspects.ContextDispatcherInterceptor.invoke(ContextDispatcherInterceptor.java:65) [pc-portlet-2.5.1.Final-redhat-1.jar:2.5.1.Final-redhat-1]
    at org.gatein.pc.portlet.PortletInvokerInterceptor.invoke(PortletInvokerInterceptor.java:111) [pc-portlet-2.5.1.Final-redhat-1.jar:2.5.1.Final-redhat-1]
    at org.exoplatform.portal.pc.aspects.PortletLifecyclePhaseInterceptor.invoke(PortletLifecyclePhaseInterceptor.java:30) [exo.portal.component.pc-3.8.16.Final-redhat-1.jar:3.8.16.Final-redhat-1]
    at org.gatein.pc.portlet.PortletInvokerInterceptor.invoke(PortletInvokerInterceptor.java:111) [pc-portlet-2.5.1.Final-redhat-1.jar:2.5.1.Final-redhat-1]
    at org.gatein.pc.portlet.aspects.SecureTransportInterceptor.invoke(SecureTransportInterceptor.java:69) [pc-portlet-2.5.1.Final-redhat-1.jar:2.5.1.Final-redhat-1]
    at org.gatein.pc.portlet.PortletInvokerInterceptor.invoke(PortletInvokerInterceptor.java:111) [pc-portlet-2.5.1.Final-redhat-1.jar:2.5.1.Final-redhat-1]
    at org.gatein.pc.portlet.aspects.ValveInterceptor.invoke(ValveInterceptor.java:84) [pc-portlet-2.5.1.Final-redhat-1.jar:2.5.1.Final-redhat-1]
    at org.gatein.pc.portlet.PortletInvokerInterceptor.invoke(PortletInvokerInterceptor.java:111) [pc-portlet-2.5.1.Final-redhat-1.jar:2.5.1.Final-redhat-1]
    at org.gatein.pc.portlet.container.ContainerPortletInvoker.invoke(ContainerPortletInvoker.java:131) [pc-portlet-2.5.1.Final-redhat-1.jar:2.5.1.Final-redhat-1]
    at org.gatein.pc.portlet.PortletInvokerInterceptor.invoke(PortletInvokerInterceptor.java:111) [pc-portlet-2.5.1.Final-redhat-1.jar:2.5.1.Final-redhat-1]
    at org.gatein.pc.portlet.state.producer.ProducerPortletInvoker.invoke(ProducerPortletInvoker.java:263) [pc-portlet-2.5.1.Final-redhat-1.jar:2.5.1.Final-redhat-1]
    at org.gatein.pc.federation.impl.FederatedPortletInvokerService.invoke(FederatedPortletInvokerService.java:163) [pc-federation-2.5.1.Final-redhat-1.jar:2.5.1.Final-redhat-1]
    at org.gatein.pc.federation.impl.FederatingPortletInvokerService.invoke(FederatingPortletInvokerService.java:246) [pc-federation-2.5.1.Final-redhat-1.jar:2.5.1.Final-redhat-1]
    at org.gatein.pc.portlet.PortletInvokerInterceptor.invoke(PortletInvokerInterceptor.java:111) [pc-portlet-2.5.1.Final-redhat-1.jar:2.5.1.Final-redhat-1]
    at org.gatein.pc.portlet.aspects.PortletCustomizationInterceptor.invoke(PortletCustomizationInterceptor.java:76) [pc-portlet-2.5.1.Final-redhat-1.jar:2.5.1.Final-redhat-1]
    at org.gatein.pc.portlet.PortletInvokerInterceptor.invoke(PortletInvokerInterceptor.java:111) [pc-portlet-2.5.1.Final-redhat-1.jar:2.5.1.Final-redhat-1]
    at org.gatein.pc.portlet.aspects.ConsumerCacheInterceptor.invoke(ConsumerCacheInterceptor.java:247) [pc-portlet-2.5.1.Final-redhat-1.jar:2.5.1.Final-redhat-1]
    at org.gatein.pc.portlet.PortletInvokerInterceptor.invoke(PortletInvokerInterceptor.java:111) [pc-portlet-2.5.1.Final-redhat-1.jar:2.5.1.Final-redhat-1]
    at org.exoplatform.portal.webui.application.UIPortlet.invoke(UIPortlet.java:1014) [exo.portal.webui.portal-3.8.16.Final-redhat-1.jar:3.8.16.Final-redhat-1]
    at org.exoplatform.portal.webui.application.UIPortletActionListener$ProcessActionActionListener.execute(UIPortletActionListener.java:117) [exo.portal.webui.portal-3.8.16.Final-redhat-1.jar:3.8.16.Final-redhat-1]

It is difficult to reproduce but it seems that it tends to occur from time to time when the server is under more load.