<zk>
	<tabbox height="500px" width="500px">
		<custom-attributes org.zkoss.zul.client.rod="false" />
		<tabs>
			<tab label="Definition" />
			<tab label="Discovery" />
		</tabs>
		<tabpanels>
			<tabpanel></tabpanel>
			<tabpanel>
				<borderlayout>
					<north>
						<window title="x" vflex="1" border="normal"></window>
					</north>
					
					<center >
						<window title="x" vflex="1" border="normal"></window>
					</center>
					
				</borderlayout>
			</tabpanel>
		</tabpanels>
	</tabbox>
</zk>