spring高手如内，关于配置事务出现的问题
前不久刚从hibernate2下升级到hibernate3下，结果发现事务配置部分不能再用了。
配置的代码是（把原来hibernate2的org.springframework.orm.hibernate.HibernateTransactionManager换成了org.springframework.orm.hibernate3.HibernateTransactionManager就不行了）
<bean   id= "transactionManager "   class= "org.springframework.orm.hibernate3.HibernateTransactionManager ">
                <property   name= "sessionFactory "> <ref   local= "sessionFactory "/> </property>
        </bean>

<bean   id= "baseTxProxy "   lazy-init= "true "   class= "org.springframework.transaction.interceptor.TransactionProxyFactoryBean ">
<property   name= "transactionManager ">
<ref   bean= "transactionManager "   />
</property>

<property   name= "transactionAttributes ">
<props>
<prop   key= "save* "> PROPAGATION_REQUIRED </prop>
<prop   key= "remove* "> PROPAGATION_REQUIRED </prop>
<prop   key= "del* "> PROPAGATION_REQUIRED </prop>
<prop   key= "load* "> PROPAGATION_REQUIRED,readOnly </prop>
<prop   key= "get* "> PROPAGATION_REQUIRED,readOnly </prop>
<prop   key= "sel* "> PROPAGATION_REQUIRED,readOnly </prop>
<prop   key= "insert* "> PROPAGATION_REQUIRED </prop>
<prop   key= "update* "> PROPAGATION_REQUIRED </prop>
<prop   key= "add* "> PROPAGATION_REQUIRED </prop>
</props>
</property>
</bean>
结果运行报错：
org.springframework.beans.factory.BeanCreationException:   Error   creating   bean   with   name   'abstractTxDefinition '   defined   in   ServletContext   resource   [/WEB-INF/config/applicationContext-hibernate.xml]:   Initialization   of   bean   failed;   nested   exception   is   java.lang.IllegalArgumentException:   'target '   is   required
java.lang.IllegalArgumentException:   'target '   is   required
请问高人这是为什么呀？郁闷

------解决方案--------------------
<bean id= "txManager " class= "org.springframework.orm.hibernate3.HibernateTransactionManager ">
<property name= "sessionFactory " ref= "sessionFactory "/>
</bean>
<bean id= "recruiterAutospotService "
class= "org.springframework.transaction.interceptor.TransactionProxyFactoryBean ">
<property name= "transactionManager ">
<ref bean= "txManager "/>
</property>
<property name= "target ">
<ref bean= "recruiterAutospotServiceImpl "/>
</property>
<property name= "transactionAttributeSource ">
<ref bean= "transactionAttributeSource "/>
</property>
</bean>