关于springMVC传值的一个小问题

最近在自学springMVC，搭建好环境之后遇到了一个通过ModelAndVIew传值的问题，在本已经测试过了，可以进入Controller类，且debug后ModelAndVIew中的msg有值，但是，在jsp取出的值却为空，代码如下,请进来的大侠们帮忙解答一下，小弟不胜感激。。

springMVC-serlet.xml

<?xml version="1.0" encoding="UTF-8"?>

<beans xmlns="http://www.springframework.org/schema/beans"

	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p"

	xmlns:context="http://www.springframework.org/schema/context"

	xmlns:mvc="http://www.springframework.org/schema/mvc"

	xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd   

       http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.0.xsd

       http://www.springframework.org/schema/mvc

       http://www.springframework.org/schema/mvc/spring-mvc.xsd   

       http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.0.xsd   

       http://www.springframework.org/schema/context 

       http://www.springframework.org/schema/context/spring-context-3.0.xsd">



	<!-- 设置使用注解的类所在的jar包 -->

	<context:annotation-config />

	<mvc:annotation-driven />

	<context:component-scan base-package="controller"></context:component-scan>

	<!-- ViewResolver -->

	<bean

		class="org.springframework.web.servlet.view.InternalResourceViewResolver">

		<property name="viewClass"

			value="org.springframework.web.servlet.view.JstlView" />

		<property name="prefix" value="/WEB-INF/jsp/" />

		<property name="suffix" value=".jsp" />

	</bean>



</beans>

indexController.java

package controller;



import javax.servlet.http.HttpServletRequest;



import org.springframework.stereotype.Controller;

import org.springframework.web.bind.annotation.RequestMapping;

import org.springframework.web.portlet.ModelAndView;



@Controller

public class indexController {

	

	@RequestMapping(value = "/index")

	public ModelAndView index(HttpServletRequest request){

		int i = 0;

		i = i + 1;

		System.out.println("index controller");

		ModelAndView modelAndView = new ModelAndView();

		modelAndView.addObject("msg", "hello world");

		modelAndView.setView("WEB-INF/jsp/index.jsp");

		return modelAndView;

		

	}

	



}

index.jsp

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"

    pageEncoding="ISO-8859-1"%>

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">

<html>

<head>

<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">

<title>springMVC</title>

</head>

<body>

	${msg}

</body>

</html>

上面就是使用的代码，访问后可以打开jsp网页，但是${msg}为空，为什么啊？