一个关于JFreeChar的错误，大侠们帮忙啊

最近项目需要用到jfreechar画图，我的环境是jb9,用的是jfreechart-0.9.20的版本。我在jb9的Configure Libraies引了三个包\jfreechart-0.9.20\lib\jcommon-0.9.5.jar,
\jfreechart-0.9.20\lib\jfreechart-0.9.20.jar，\jfreechart-0.9.20\lib\jfreechart-0.9.20-demo.jar
然后又在jb9下Project Properties\required libraries把这三个包引进工程了。可是，现在工程起不来了。晕了。
错误提示是：
type Exception report

message Internal Server Error

description The server encountered an internal error (Internal Server Error) that prevented it from fulfilling this request.

exception

javax.servlet.ServletException: Servlet.init() for servlet action threw exception
at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:946)
at org.apache.catalina.core.StandardWrapper.allocate(StandardWrapper.java:655)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:214)
at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:190)
at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566)
at org.apache.catalina.valves.CertificatesValve.invoke(CertificatesValve.java:246)
at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:564)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943)
at org.apache.catalina.core.StandardContext.invoke(StandardContext.java:2347)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:180)
at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566)
at org.apache.catalina.valves.ErrorDispatcherValve.invoke(ErrorDispatcherValve.java:170)
at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:564)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:170)
at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:564)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:174)
at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943)
at org.apache.catalina.connector.http.HttpProcessor.process(HttpProcessor.java:1027)
at org.apache.catalina.connector.http.HttpProcessor.run(HttpProcessor.java:1125)
at java.lang.Thread.run(Thread.java:536)

root cause

java.lang.NoClassDefFoundError: org/xml/sax/ext/Attributes2
at java.lang.ClassLoader.defineClass0(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:502)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:123)
at org.apache.catalina.loader.WebappClassLoader.findClassInternal(WebappClassLoader.java:1643)
at org.apache.catalina.loader.WebappClassLoader.findClass(WebappClassLoader.java:937)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1372)
at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1254)
at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:315)
at gnu.xml.aelfred2.XmlReader.(XmlReader.java:67)
at gnu.xml.aelfred2.JAXPFactory$JaxpParser.(JAXPFactory.java:140)
at gnu.xml.aelfred2.JAXPFactory.newSAXParser(JAXPFactory.java:66)
at org.apache.commons.digester.Digester.getParser(Digester.java:686)
at org.apache.commons.digester.Digester.getXMLReader(Digester.java:902)
at org.apache.commons.digester.Digester.parse(Digester.java:1567)
at org.apache.struts.action.ActionServlet.initServlet(ActionServlet.java:1433)
at org.apache.struts.action.ActionServlet.init(ActionServlet.java:466)
at javax.servlet.GenericServlet.init(GenericServlet.java:256)
at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:918)
at org.apache.catalina.core.StandardWrapper.allocate(StandardWrapper.java:655)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:214)
at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:190)
at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566)
at org.apache.catalina.valves.CertificatesValve.invoke(CertificatesValve.java:246)
at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:564)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943)
at org.apache.catalina.core.StandardContext.invoke(StandardContext.java:2347)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:180)
at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566)
at org.apache.catalina.valves.ErrorDispatcherValve.invoke(ErrorDispatcherValve.java:170)
at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:564)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:170)
at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:564)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:174)
at org.apache.catalina.core.StandardPipeline.invokeNext(StandardPipeline.java:566)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:472)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:943)
at org.apache.catalina.connector.http.HttpProcessor.process(HttpProcessor.java:1027)
at org.apache.catalina.connector.http.HttpProcessor.run(HttpProcessor.java:1125)
at java.lang.Thread.run(Thread.java:536)