I would like to use ajax. Now I get a null pointer exception in ajax library.
Any ideas what is wrong here? I use the latest digester library of Apache commons.

28.03.2007 23:50:17 org.apache.catalina.core.StandardContext listenerStart
SCHWERWIEGEND: Exception sending context initialized event to listener instance of class com.sun.faces.config.ConfigureListener
javax.faces.FacesException: java.lang.NullPointerException
at org.ajax4jsf.framework.resource.ResourceBuilderImpl.registerConfig(ResourceBuilderImpl.java:175)
at org.ajax4jsf.framework.resource.ResourceBuilderImpl.registerResources(ResourceBuilderImpl.java:216)
at org.ajax4jsf.framework.resource.ResourceBuilderImpl.<init>(ResourceBuilderImpl.java:120)
at org.ajax4jsf.framework.resource.InternetResourceBuilder.getInstance(InternetResourceBuilder.java:156)
at org.ajax4jsf.framework.renderer.RendererBase.getResourceBuilder(RendererBase.java:136)
at org.ajax4jsf.framework.renderer.RendererBase.getResource(RendererBase.java:131)
at org.ajax4jsf.renderkit.html.AjaxFormRenderer.<init>(AjaxFormRenderer.java:74)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
at java.lang.reflect.Constructor.newInstance(Constructor.java:494)
at java.lang.Class.newInstance0(Class.java:350)
at java.lang.Class.newInstance(Class.java:303)
at com.sun.faces.config.ConfigureListener.configure(ConfigureListener.java:1061)
at com.sun.faces.config.ConfigureListener.configure(ConfigureListener.java:1133)
at com.sun.faces.config.ConfigureListener.configure(ConfigureListener.java:543)
at com.sun.faces.config.ConfigureListener.contextInitialized(ConfigureListener.java:436)
at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:3763)
at org.apache.catalina.core.StandardContext.start(StandardContext.java:4211)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:759)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:739)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:524)
at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:904)
at org.apache.catalina.startup.HostConfig.deployDirectories(HostConfig.java:867)
at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:474)
at org.apache.catalina.startup.HostConfig.start(HostConfig.java:1122)
at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:310)
at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:119)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1021)
at org.apache.catalina.core.StandardHost.start(StandardHost.java:718)
at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1013)
at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:442)
at org.apache.catalina.core.StandardService.start(StandardService.java:450)
at org.apache.catalina.core.StandardServer.start(StandardServer.java:709)
at org.apache.catalina.startup.Catalina.start(Catalina.java:551)
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:585)
at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:294)
at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:432)
Caused by: java.lang.NullPointerException
at org.apache.commons.digester.Digester.createSAXException(Digester.java:2540)
at org.apache.commons.digester.Digester.createSAXException(Digester.java:2566)
at org.apache.commons.digester.Digester.endElement(Digester.java:1061)
at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.endElement(AbstractSAXParser.java:633)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanEndElement(XMLDocumentFragmentScannerImpl.java:1241)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl$FragmentContentDispatcher.dispatch(XMLDocumentFragmentScannerImpl.java:1685)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(XMLDocumentFragmentScannerImpl.java:368)
at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:834)
at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:764)
at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(XMLParser.java:148)
at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(AbstractSAXParser.java:1242)
at org.apache.commons.digester.Digester.parse(Digester.java:1567)
at org.ajax4jsf.framework.resource.ResourceBuilderImpl.registerConfig(ResourceBuilderImpl.java:162)
... 40 more