<zk>
	<tabbox selectedIndex="1">
		<tabs >
			<tab label="Tab1" />
			<tab label="Tab2" />
			<tab label="Tab3" />
		</tabs>
		<tabpanels>
			<tabpanel>Panel1</tabpanel>
			<tabpanel>Panel2</tabpanel>
			<tabpanel>Panel3</tabpanel>
		</tabpanels>
	</tabbox>
</zk>

java.lang.IllegalStateException: No tab at all
	at org.zkoss.zul.Tabbox.setSelectedIndex(Tabbox.java:162)
	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 org.zkoss.zk.ui.metainfo.Property.assign0(Property.java:284)
	at org.zkoss.zk.ui.metainfo.Property.assign(Property.java:169)
	at org.zkoss.zk.ui.metainfo.ComponentInfo.applyProperties(ComponentInfo.java:729)
	at org.zkoss.zk.ui.impl.AbstractUiFactory.newComponent(AbstractUiFactory.java:106)
	at org.zkoss.zk.ui.impl.UiEngineImpl.execCreateChild0(UiEngineImpl.java:801)
	at org.zkoss.zk.ui.impl.UiEngineImpl.execCreateChild(UiEngineImpl.java:771)
	at org.zkoss.zk.ui.impl.UiEngineImpl.execCreate0(UiEngineImpl.java:680)
	at org.zkoss.zk.ui.impl.UiEngineImpl.execCreateChild(UiEngineImpl.java:743)
	at org.zkoss.zk.ui.impl.UiEngineImpl.execCreate0(UiEngineImpl.java:702)
	at org.zkoss.zk.ui.impl.UiEngineImpl.execCreate(UiEngineImpl.java:643)
	at org.zkoss.zk.ui.impl.UiEngineImpl.execNewPage0(UiEngineImpl.java:396)
	at org.zkoss.zk.ui.impl.UiEngineImpl.execNewPage(UiEngineImpl.java:316)
	at org.zkoss.zk.ui.http.DHtmlLayoutServlet.process(DHtmlLayoutServlet.java:215)
	at org.zkoss.zk.ui.http.DHtmlLayoutServlet.doGet(DHtmlLayoutServlet.java:135)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:707)
	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$RequestHandler.headerComplete(HttpConnection.java:928)
	at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:549)
	at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:212)
	at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404)
	at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:410)
	at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:582)