困扰我一下午的webwork问题，高手赐教！！

页面报错：
com.opensymphony.xwork.config.ConfigurationException: There is no Action mapped for action name login
com.opensymphony.xwork.DefaultActionProxy.<init>(DefaultActionProxy.java:73)
com.opensymphony.xwork.DefaultActionProxyFactory.createActionProxy(DefaultActionProxyFactory.java:45)
com.opensymphony.webwork.dispatcher.ServletDispatcher.serviceAction(ServletDispatcher.java:270)
com.opensymphony.webwork.dispatcher.ServletDispatcher.service(ServletDispatcher.java:237)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)------------------
Tomcat报错：
2008-6-21 20:43:49 com.opensymphony.xwork.config.providers.XmlConfigurationProvider addAction
严重: Action class [com.sotier.webwork.web.LoginAction] not found, skipping action [login]
java.lang.ClassCastException: com.sotier.webwork.web.LoginAction
at com.opensymphony.xwork.ObjectFactory.buildAction(ObjectFactory.java:87)
at com.opensymphony.xwork.config.providers.XmlConfigurationProvider.addAction(XmlConfigurationProvider.java:168)
at com.opensymphony.xwork.config.providers.XmlConfigurationProvider.addPackage(XmlConfigurationProvider.java:228)
at com.opensymphony.xwork.config.providers.XmlConfigurationProvider.loadConfigurationFile(XmlConfigurationProvider.java:567)
at com.opensymphony.xwork.config.providers.XmlConfigurationProvider.init(XmlConfigurationProvider.java:124)
at com.opensymphony.xwork.config.impl.DefaultConfiguration.reload(DefaultConfiguration.java:85)
at com.opensymphony.xwork.config.ConfigurationManager.getConfiguration(ConfigurationManager.java:56)
at com.opensymphony.xwork.DefaultActionProxyFactory.setupConfigIfActionIsCommand(DefaultActionProxyFactory.java:58)
at com.opensymphony.xwork.DefaultActionProxyFactory.createActionProxy(DefaultActionProxyFactory.java:43)
at com.opensymphony.webwork.dispatcher.ServletDispatcher.serviceAction(ServletDispatcher.java:270)
at com.opensymphony.webwork.dispatcher.ServletDispatcher.service(ServletDispatcher.java:237)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:237)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:157)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:214)
at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:104)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:520)
at org.apache.catalina.core.StandardContextValve.invokeInternal(StandardContextValve.java:198)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:152)
at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:104)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:520)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:137)
at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:104)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:118)
at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:102)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:520)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.core.StandardValveContext.invokeNext(StandardValveContext.java:104)
at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:520)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:929)
at org.apache.coyote.tomcat5.CoyoteAdapter.service(CoyoteAdapter.java:160)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:799)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.processConnection(Http11Protocol.java:705)
at org.apache.tomcat.util.net.TcpWorkerThread.runIt(PoolTcpEndpoint.java:577)
at org.apache.tomcat.util.threads.ThreadPool$ControlRunnable.run(ThreadPool.java:683)
at java.lang.Thread.run(Thread.java:595)==============
我的代码：
WEB-INF/web.xml<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee 
http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
<servlet>
<servlet-name>webwork</servlet-name>
<servlet-class>
com.opensymphony.webwork.dispatcher.ServletDispatcher
</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>webwork</servlet-name>
<url-pattern>*.action</url-pattern>
</servlet-mapping>
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
<taglib>
<taglib-uri>webwork</taglib-uri>
<taglib-location>/WEB-INF/webwork.tld</taglib-location>
</taglib>
</web-app>
-----------------------
xwork.xml  <!DOCTYPE xwork PUBLIC "-//OpenSymphony Group//XWork 1.0//EN"
"http://www.opensymphony.com/xwork/xwork-1.0.dtd">
<xwork>
<include file="webwork-default.xml" />
<package name="default" extends="webwork-default">
<interceptors>
<interceptor-stack name="modelParamsStack">
<interceptor-ref name="params" />
<interceptor-ref name="model-driven" />
</interceptor-stack>
</interceptors>
<action name="login"
class="com.sotier.webwork.web.LoginAction">
<result name="success" type="dispatcher">
<param name="location">/main.jsp</param>
</result>
<result name="loginfail" type="dispatcher">
<param name="location">/index.jsp</param>
</result>
<interceptor-ref name="modelParamsStack" />
</action>
</package>
</xwork>----------------LoginAction.javapackage com.sotier.webwork.web;import java.util.Map;import com.opensymphony.xwork.ActionContext;public class LoginAction implements Action, ModelDriven
{
private static final long serialVersionUID = 1L; private final static String LOGIN_FAIL = "loginfail"; LoginInfo loginInfo = new LoginInfo(); public String execute() throws Exception
{
if ("sotier".equalsIgnoreCase(loginInfo.getUsername())
&& "111".equals(loginInfo.getPassword()))
{
// 将当前登录的用户名保存到Session
ActionContext ctx = ActionContext.getContext();
Map session = ctx.getSession();
session.put("username", loginInfo.getUsername());
return SUCCESS;
}
else
{
loginInfo.setErrorMessage("Username/Password Error!");
return LOGIN_FAIL;
}
} public Object getModel()
{
return loginInfo;
}}---------------
Action 接口：package com.sotier.webwork.web;import java.io.Serializable;public interface Action extends Serializable
{
public static final String SUCCESS = "success"; public static final String NONE = "none"; public static final String ERROR = "error"; public static final String INPUT = "input"; public static final String LOGIN = "login"; public String execute() throws Exception;
}
-------------
ModelDriven 接口：package com.sotier.webwork.web;public interface ModelDriven
{
Object getModel();
}-------------
index.jsp<%@ page language="java" import="java.util.*" pageEncoding="ISO-8859-1"%>
<html>
<body>
<form name="okform" action="<%=request.getContextPath ()%>/login.action">
<p align="center">
Login
<br>
<ww:if test="errorMessage != null">
<font color="red"> <ww:property value="errorMessage" /> </font>
</ww:if>
</p>
UserName:
<input type="text" name="model.username" />
<br>
PassWord:
<input type="password" name="model.password" />
<br>
<p align="center">
<input type="submit" value="Submit" name="B1" />
<input type="reset" value="Reset" name="B2" />
</p>
</form>
</body>
</html>可急死我了 ， 在线等！！