exception thrown before lock:

2009-12-11 14:03:10,406 ERROR [org.apache.jackrabbit.core.observation.ObservationDispatcher] Synchronous EventConsumer threw exception.
java.lang.NullPointerException
        at org.hippoecm.repository.security.HippoAccessManager.getItemState(HippoAccessManager.java:936)
        at org.hippoecm.repository.security.HippoAccessManager.canRead(HippoAccessManager.java:467)
        at org.hippoecm.repository.security.HippoAccessManager.canRead(HippoAccessManager.java:427)
        at org.apache.jackrabbit.core.observation.EventConsumer.canRead(EventConsumer.java:296)
        at org.apache.jackrabbit.core.observation.EventConsumer.consumeEvents(EventConsumer.java:228)
        at org.apache.jackrabbit.core.observation.ObservationDispatcher.dispatchEvents(ObservationDispatcher.java:201)
        at org.apache.jackrabbit.core.observation.EventStateCollection.dispatch(EventStateCollection.java:422)
        at org.apache.jackrabbit.core.observation.DelegatingObservationDispatcher.dispatch(DelegatingObservationDispatcher.java:123)
        at org.apache.jackrabbit.core.observation.DelegatingObservationDispatcher.dispatchEvents(DelegatingObservationDispatcher.java:99)
        at org.apache.jackrabbit.core.observation.EventStateCollection.dispatch(EventStateCollection.java:422)
        at org.apache.jackrabbit.core.state.SharedItemStateManager$Update.end(SharedItemStateManager.java:754)
        at org.apache.jackrabbit.core.state.SharedItemStateManager.update(SharedItemStateManager.java:1100)
        at org.apache.jackrabbit.core.state.LocalItemStateManager.update(LocalItemStateManager.java:351)
        at org.apache.jackrabbit.core.state.LocalItemStateManager.update(LocalItemStateManager.java:326)
        at org.apache.jackrabbit.core.version.AbstractVersionManager$WriteOperation.save(AbstractVersionManager.java:150)
        at org.apache.jackrabbit.core.version.AbstractVersionManager.createVersionHistory(AbstractVersionManager.java:317)
        at org.apache.jackrabbit.core.version.VersionManagerImpl$1.run(VersionManagerImpl.java:220)
        at org.apache.jackrabbit.core.version.VersionManagerImpl$DynamicESCFactory.doSourced(VersionManagerImpl.java:567)
        at org.apache.jackrabbit.core.version.VersionManagerImpl.createVersionHistory(VersionManagerImpl.java:217)
        at org.apache.jackrabbit.core.version.XAVersionManager.createVersionHistory(XAVersionManager.java:156)
        at org.apache.jackrabbit.core.version.AbstractVersionManager.getVersionHistory(AbstractVersionManager.java:234)
        at org.apache.jackrabbit.core.ItemImpl.initVersionHistories(ItemImpl.java:727)
        at org.apache.jackrabbit.core.ItemImpl.save(ItemImpl.java:1080)
        at org.apache.jackrabbit.core.SessionImpl.save(SessionImpl.java:858)
        at org.hippoecm.repository.decorating.SessionDecorator.save(SessionDecorator.java:202)
        at org.hippoecm.repository.impl.SessionDecorator.save(SessionDecorator.java:173)
        at org.hippoecm.repository.standardworkflow.FolderWorkflowImpl.add(FolderWorkflowImpl.java:248)
        at org.hippoecm.repository.standardworkflow.FolderWorkflowImpl.add(FolderWorkflowImpl.java:180)
        at sun.reflect.GeneratedMethodAccessor36.invoke(Unknown Source)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:597)
        at org.hippoecm.repository.impl.WorkflowManagerImpl$WorkflowInvocationHandler.invoke(WorkflowManagerImpl.java:496)
        at $Proxy2.add(Unknown Source)
        at org.hippoecm.frontend.plugins.standardworkflow.FolderWorkflowPlugin$4.execute(FolderWorkflowPlugin.java:242)
        at org.hippoecm.frontend.plugins.standardworkflow.FolderWorkflowPlugin$4.execute(FolderWorkflowPlugin.java:218)
        at org.hippoecm.addon.workflow.CompatibilityWorkflowPlugin$WorkflowAction.execute(CompatibilityWorkflowPlugin.java:166)
        at org.hippoecm.addon.workflow.CompatibilityWorkflowPlugin$WorkflowAction$WorkflowDialog.execute(CompatibilityWorkflowPlugin.java:241)
        at org.hippoecm.addon.workflow.CompatibilityWorkflowPlugin$WorkflowAction$WorkflowDialog.onOk(CompatibilityWorkflowPlugin.java:225)
        at org.hippoecm.frontend.dialog.AbstractDialog.handleSubmit(AbstractDialog.java:523)
        at org.hippoecm.frontend.dialog.AbstractDialog$2.onSubmit(AbstractDialog.java:390)
        at org.hippoecm.frontend.dialog.AbstractDialog$ButtonWrapper$1.onSubmit(AbstractDialog.java:264)
        at org.apache.wicket.ajax.markup.html.form.AjaxButton$1.onSubmit(AjaxButton.java:86)
        at org.apache.wicket.ajax.form.AjaxFormSubmitBehavior.onEvent(AjaxFormSubmitBehavior.java:128)
        at org.apache.wicket.ajax.AjaxEventBehavior.respond(AjaxEventBehavior.java:163)
        at org.apache.wicket.ajax.AbstractDefaultAjaxBehavior.onRequest(AbstractDefaultAjaxBehavior.java:297)
        at org.apache.wicket.request.target.component.listener.BehaviorRequestTarget.processEvents(BehaviorRequestTarget.java:100)
        at org.apache.wicket.request.AbstractRequestCycleProcessor.processEvents(AbstractRequestCycleProcessor.java:91)
        at org.hippoecm.frontend.PluginRequestCycleProcessor.processEvents(PluginRequestCycleProcessor.java:31)
        at org.apache.wicket.RequestCycle.processEventsAndRespond(RequestCycle.java:1175)
        at org.apache.wicket.RequestCycle.step(RequestCycle.java:1252)
        at org.apache.wicket.RequestCycle.steps(RequestCycle.java:1353)
        at org.apache.wicket.RequestCycle.request(RequestCycle.java:493)
        at org.apache.wicket.protocol.http.WicketFilter.doGet(WicketFilter.java:355)
        at org.apache.wicket.protocol.http.WicketServlet.doPost(WicketServlet.java:145)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:727)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)
        at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511)
        at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1166)
        at org.hippoecm.frontend.plugins.login.ConcurrentLoginFilter.doFilter(ConcurrentLoginFilter.java:54)
        at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157)
        at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:388)
        at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216)
        at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182)
        at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:765)
        at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:418)
        at org.mortbay.jetty.handler.ContextHandlerCollection.handle(ContextHandlerCollection.java:230)
        at org.mortbay.jetty.handler.HandlerCollection.handle(HandlerCollection.java:114)
        at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152)
        at org.mortbay.jetty.Server.handle(Server.java:326)
        at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542)
        at org.mortbay.jetty.HttpConnection$RequestHandler.content(HttpConnection.java:938)
        at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:755)
        at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:218)
        at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)
        at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:409)
        at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:582)