Error creating bean with name 'dataSource' defined in ServletContext resource [/

applicationContext.xml 如下：<?xml version="1.0" encoding="UTF-8"?>
<beans
xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd">
<bean id="dataSource"
class="org.springframework.jndi.JndiObjectFactoryBean">
<property name="jndiName" value="java:comp/env/jdbc/mldn"></property>
</bean>
<bean id="sessionFactory"
class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">
<property name="dataSource">
<ref bean="dataSource" />
</property>
<property name="hibernateProperties">
<props>
<prop key="hibernate.dialect">
org.hibernate.dialect.MySQLDialect
</prop>
<!-- 表示允许自动提交 -->
<prop key="hibernate.connection.autocommit">true</prop>
<!-- 显示sql语句 -->
<prop key="hibernate.show_sql">true</prop>
</props>
</property>
</bean>
<bean id="hibernateTemplate"
class="org.springframework.orm.hibernate3.HibernateTemplate">
<property name="sessionFactory">
<ref bean="sessionFactory" />
</property>
</bean>
</beans>请问什么地方出现问题了 急！！！！！！！！！！！！