webwork入门问题求教
小弟新学webwork不久，遇到困难了，希望指教。  
服务器用的是tomcat5.0,webwork用的是最新的2.2.5，文件夹名字叫做mywebwork。  
在运行的时候，输入网址，可以访问首页，但是按按钮的时候就提示出错了。出错内容如下：  
################################################################################  
type   Exception   report  
message  
description   The   server   encountered   an   internal   error   ()   that   prevented   it   from   fulfilling   this   request.  
exception  
javax.servlet.ServletException:   Servlet   execution   threw   an   exception  
root   cause  
javax.xml.transform.TransformerFactoryConfigurationError:   Provider   org.apache.xalan.processor.TransformerFactoryImpl   not   found  
javax.xml.transform.TransformerFactory.newInstance(Unknown   Source)  
com.opensymphony.xwork.util.DomHelper$DOMBuilder. <clinit> (DomHelper.java:168)  
com.opensymphony.xwork.util.DomHelper.parse(DomHelper.java:116)  
com.opensymphony.xwork.config.providers.XmlConfigurationProvider.loadConfigurationFile(XmlConfigurationProvider.java:650)  
com.opensymphony.xwork.config.providers.XmlConfigurationProvider.init(XmlConfigurationProvider.java:91)  
com.opensymphony.xwork.config.impl.DefaultConfiguration.reload(DefaultConfiguration.java:85)  
com.opensymphony.xwork.config.ConfigurationManager.getConfiguration(ConfigurationManager.java:54)  
com.opensymphony.xwork.DefaultActionProxy. <init> (DefaultActionProxy.java:60)  
com.opensymphony.xwork.DefaultActionProxyFactory.createActionProxy(DefaultActionProxyFactory.java:46)  
com.opensymphony.webwork.dispatcher.DispatcherUtils.serviceAction(DispatcherUtils.java:216)  
com.opensymphony.webwork.dispatcher.ServletDispatcher.service(ServletDispatcher.java:111)  
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)

note   The   full   stack   trace   of   the   root   cause   is   available   in   the   Apache   Tomcat/5.0.30   logs.

###############################################################################  
目录结构如下：（[]里面表示目录，不会传图片，就这样表示了，有些凌乱，请包涵^_^）  
--[mywebwork]  
--index.jsp  
--success.jsp  
--input.jsp  
--[WEB-INF]  
--webwork.xml  
--[lib]  
--commons-logging.jar,ognl.jar,oscore.jar，rife-continuations.jar,xwork.jar,freemarker.jar,javamail.jar,webwork-2.2.5.jar,velocity-dep.jar  
--[classes]  
--webwork.properties  
--xwork.xml  
--[edu]  
--[hktz]  
--WebworkTry.class  
--[src]  
--[edu]  
--[hktz]  
--WebworkTry.java  
#################################################################################  
webwork.xml内容如下：  
<?xml   version= "1.0 "   encoding= "ISO-8859-1 "?>  
<web-app   xmlns= "http://java.sun.com/xml/ns/j2ee "  
xmlns:xsi= "http://www.w3.org/2001/XMLSchema-instance "  
xsi:schemaLocation= "http://java.sun.com/xml/ns/j2ee   http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd "  
version= "2.4 ">

<display-name> Welcome   to   Tomcat </display-name>  
<description>  
Welcome   to   Tomcat &nbs