spring3+hibernate4 出现的一个问题
错误是这样的：
当我单独测试dao的时候，会报错：No Session found for current thread
但是把到加入到service时，再测试，就没问题
配置文件如下：

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

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

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

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

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

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



       xsi:schemaLocation="http://www.springframework.org/schema/beans

       http://www.springframework.org/schema/beans/spring-beans-2.5.xsd

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

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

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

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

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

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

       ">

    <context:annotation-config/>

    <context:component-scan base-package="com.zq"/>

    <bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource">

        <property name="driverClassName" value="net.sourceforge.jtds.jdbc.Driver"></property>

        <property name="url" value="jdbc:mysql://localhost:3306/test"></property>

        <property name="username" value="root"></property>

        <property name="password" value="123456"></property>

        <property name="initialSize" value="10"></property>

        <property name="maxActive" value="1000"></property>

        <property name="maxIdle" value="300"></property>

        <property name="minIdle" value="10"></property>

        <property name="maxWait" value="10000"></property>

        <!--<property name="removeAbandoned" value="true" />

        <property name="removeAbandonedTimeout" value="60"/>

        <property name="logAbandoned" value="true" />

        <property name="testOnBorrow" value="true"/>

        <property name="testWhileIdle" value="true"/>

        <property name="validationQuery" value="select getdate()"/>-->

    </bean>

    <!--整合hibernate-->

    <bean id="sessionFactory