Problem to start PerformanceMeter

SCHWERWIEGEND: Unable to load a listenr, [SYS jndi:/localhost/scomobil/WEB-INF/zk.xml line 20 col 12]
java.lang.InstantiationException: org.zkoss.zk.ui.util.PerformanceMeter
	at java.lang.Class.newInstance0(Class.java:340)
	at java.lang.Class.newInstance(Class.java:308)
	at org.zkoss.zk.ui.util.Configuration.getInstance(Configuration.java:364)
	at org.zkoss.zk.ui.util.Configuration.addListener(Configuration.java:235)
	at org.zkoss.zk.ui.sys.ConfigParser.parseListener(ConfigParser.java:262)
	at org.zkoss.zk.ui.sys.ConfigParser.parse(ConfigParser.java:301)
	at org.zkoss.zk.ui.sys.ConfigParser.parse(ConfigParser.java:277)
	at org.zkoss.zk.ui.http.WebManager.<init>(WebManager.java:157)
	at org.zkoss.zk.ui.http.DHtmlLayoutServlet.init(DHtmlLayoutServlet.java:108)
	at javax.servlet.GenericServlet.init(GenericServlet.java:212)
	at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1173)
	at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:993)
	at org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.java:4149)
	at org.apache.catalina.core.StandardContext.start(StandardContext.java:4458)
	at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:791)
	at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:771)
	at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:526)
	at org.apache.catalina.startup.HostConfig.deployDescriptor(HostConfig.java:630)
	at org.apache.catalina.startup.HostConfig.deployDescriptors(HostConfig.java:556)
	at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:491)
	at org.apache.catalina.startup.HostConfig.start(HostConfig.java:1206)
	at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:314)
	at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:119)
	at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1053)
	at org.apache.catalina.core.StandardHost.start(StandardHost.java:722)
	at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1045)
	at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:443)
	at org.apache.catalina.core.StandardService.start(StandardService.java:516)
	at org.apache.catalina.core.StandardServer.start(StandardServer.java:710)
	at org.apache.catalina.startup.Catalina.start(Catalina.java:583)
	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.apache.catalina.startup.Bootstrap.start(Bootstrap.java:288)
	at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:413)

<zk>
	<device-config>
		<device-type>ajax</device-type>
		<timeout-uri>/timeout.zul</timeout-uri><!-- An empty URL can cause the browser to reload the same URL -->
	</device-config>
	<!-- Programmablauf gestoppt bis doModal beendet!  -->
	<system-config>
		<disable-event-thread >false</disable-event-thread>
	</system-config>
	<listener>
		<description>Monitor the statistic</description>
		<listener-class>org.zkoss.zk.ui.util.Statistic</listener-class>
	</listener>
	<listener>
		<description>ZK performance monitor</description>
		<listener-class>org.zkoss.zk.ui.util.PerformanceMeter</listener-class>
	</listener>
</zk>