java.lang.IllegalStateException: UI can't be modified in the rendering phase
	at org.zkoss.zk.ui.impl.UiVisualizer.getAttrRespMap(UiVisualizer.java:299)
	at org.zkoss.zk.ui.impl.UiVisualizer.addSmartUpdate0(UiVisualizer.java:254)
	at org.zkoss.zk.ui.impl.UiVisualizer.addSmartUpdate(UiVisualizer.java:238)
	at org.zkoss.zk.ui.impl.UiEngineImpl.addSmartUpdate(UiEngineImpl.java:280)
	at org.zkoss.zk.ui.AbstractComponent.smartUpdate(AbstractComponent.java:1575)
	at org.zkoss.zk.ui.AbstractComponent.smartUpdate(AbstractComponent.java:1550)
	at org.zkoss.zk.ui.AbstractComponent.removeEventListener(AbstractComponent.java:2148)
	at org.zkoss.bind.impl.BinderImpl.removeEventCommandListenerIfExists(BinderImpl.java:1111)
	at org.zkoss.bind.impl.BinderImpl.removeBindings(BinderImpl.java:1698)
	at org.zkoss.bind.impl.BinderImpl.removeBindings(BinderImpl.java:1668)
	at org.zkoss.bind.tracker.impl.BindUiLifeCycle.removeBindings0(BindUiLifeCycle.java:123)
	at org.zkoss.bind.tracker.impl.BindUiLifeCycle.removeBindings(BindUiLifeCycle.java:106)
	at org.zkoss.bind.tracker.impl.BindUiLifeCycle.removeBindings(BindUiLifeCycle.java:110)
	at org.zkoss.bind.tracker.impl.BindUiLifeCycle.removeBindings(BindUiLifeCycle.java:110)
	at org.zkoss.bind.tracker.impl.BindUiLifeCycle.afterPageDetached(BindUiLifeCycle.java:102)
	at org.zkoss.zk.ui.util.Configuration.afterPageDetached(Configuration.java:1123)
	at org.zkoss.zk.ui.impl.DesktopImpl.removePage(DesktopImpl.java:811)
	at org.zkoss.zk.ui.impl.UiVisualizer.getResponses(UiVisualizer.java:621)
	at org.zkoss.zk.ui.impl.UiEngineImpl.getResponses(UiEngineImpl.java:1409)
	at org.zkoss.zk.ui.impl.UiEngineImpl.execUpdate(UiEngineImpl.java:1221)
	at org.zkoss.zk.au.http.DHtmlUpdateServlet.process(DHtmlUpdateServlet.java:583)
	at org.zkoss.zk.au.http.DHtmlUpdateServlet.doGet(DHtmlUpdateServlet.java:481)
	at org.zkoss.zk.au.http.DHtmlUpdateServlet.doPost(DHtmlUpdateServlet.java:489)
	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.handle(ServletHandler.java:401)
	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:766)
	at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:450)
	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$RequestHandler.content(HttpConnection.java:945)
	at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:756)
	at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:218)
	at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)
	at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:410)
	at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:582)