activiti-explorer查看节点状态错误XPath currently not supported as expressionLanguage

2013-2-3 15:31:50 org.activiti.engine.impl.bpmn.deployer.BpmnDeployer deploy
信息: Processing resource process60.png
2013-2-3 15:31:50 org.activiti.engine.impl.bpmn.deployer.BpmnDeployer deploy
信息: Processing resource process60.bpmn20.xml
2013-2-3 15:31:50 org.activiti.engine.impl.bpmn.parser.BpmnParse parseDefinitionsAttributes
信息: XMLSchema currently not supported as typeLanguage
2013-2-3 15:31:50 org.activiti.engine.impl.bpmn.parser.BpmnParse parseDefinitionsAttributes
信息: XPath currently not supported as expressionLanguage
2013-2-3 15:31:50 com.vaadin.Application terminalError
严重: Terminal error:
com.vaadin.event.ListenerMethod$MethodException
Cause: java.lang.NullPointerException
        at com.vaadin.event.ListenerMethod.receiveEvent(ListenerMethod.java:510)
        at com.vaadin.event.EventRouter.fireEvent(EventRouter.java:164)
        at com.vaadin.ui.AbstractComponent.fireEvent(AbstractComponent.java:1193)
        at com.vaadin.ui.AbstractField.fireValueChange(AbstractField.java:891)
        at com.vaadin.ui.AbstractField.setValue(AbstractField.java:529)
        at com.vaadin.ui.AbstractSelect.setValue(AbstractSelect.java:666)
        at com.vaadin.ui.AbstractSelect.changeVariables(AbstractSelect.java:475)
        at com.vaadin.ui.Table.changeVariables(Table.java:2038)
        at com.vaadin.terminal.gwt.server.AbstractCommunicationManager.handleVariableBurst(AbstractCommunicationManager.java:1299)
        at com.vaadin.terminal.gwt.server.AbstractCommunicationManager.handleVariables(AbstractCommunicationManager.java:1219)
        at com.vaadin.terminal.gwt.server.AbstractCommunicationManager.doHandleUidlRequest(AbstractCommunicationManager.java:735)
        at com.vaadin.terminal.gwt.server.CommunicationManager.handleUidlRequest(CommunicationManager.java:296)
        at com.vaadin.terminal.gwt.server.AbstractApplicationServlet.service(AbstractApplicationServlet.java:501)
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
        at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
        at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99)
        at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:936)
        at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
        at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407)
        at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1004)
        at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:589)
        at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.run(AprEndpoint.java:1822)
        at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:885)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:907)
        at java.lang.Thread.run(Thread.java:619)
Caused by: java.lang.NullPointerException
        at org.activiti.explorer.ui.custom.UserProfileLink.initUserLink(UserProfileLink.java:93)
        at org.activiti.explorer.ui.custom.UserProfileLink.<init>(UserProfileLink.java:61)
        at org.activiti.explorer.ui.management.processinstance.ProcessInstanceDetailPanel.getTaskAssigneeComponent(ProcessInstanceDetailPanel.java:272
)
        at org.activiti.explorer.ui.management.processinstance.ProcessInstanceDetailPanel.addTaskItem(ProcessInstanceDetailPanel.java:264)
        at org.activiti.explorer.ui.management.processinstance.ProcessInstanceDetailPanel.addTasks(ProcessInstanceDetailPanel.java:232)
        at org.activiti.explorer.ui.management.processinstance.ProcessInstanceDetailPanel.init(ProcessInstanceDetailPanel.java:112)
        at org.activiti.explorer.ui.management.processinstance.ProcessInstanceDetailPanel.<init>(ProcessInstanceDetailPanel.java:98)
        at org.activiti.explorer.ui.process.ProcessInstancePage$1.valueChange(ProcessInstancePage.java:60)
        at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:597)
        at com.vaadin.event.ListenerMethod.receiveEvent(ListenerMethod.java:490)
        ... 29 more