用spring时从没遇到的一个关于transaction的异常

从页面crud数据时大部分时间正常，但偶尔会出现下面的错误信息：

type Exception report

message 

description The server encountered an internal error () that prevented it from fulfilling this request.

exception 

javax.servlet.ServletException: Pre-bound JDBC Connection found - HibernateTransactionManager does not support running within DataSourceTransactionManager if told to manage the DataSource itself. It is recommended to use a single HibernateTransactionManager for all transactions on a single DataSource, no matter whether Hibernate or JDBC access.
	org.apache.struts.action.RequestProcessor.processException(RequestProcessor.java:523)
	org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:421)
	org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:224)
	org.apache.struts.action.ActionServlet.process(ActionServlet.java:1194)
	org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:414)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:689)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
	com.taiji.bms.web.filter.SsoFilter.doFilter(SsoFilter.java:64)
	org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:75)
	org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
	org.springframework.orm.hibernate3.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:174)
	org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)


root cause 

org.springframework.transaction.IllegalTransactionStateException: Pre-bound JDBC Connection found - HibernateTransactionManager does not support running within DataSourceTransactionManager if told to manage the DataSource itself. It is recommended to use a single HibernateTransactionManager for all transactions on a single DataSource, no matter whether Hibernate or JDBC access.
	org.springframework.orm.hibernate3.HibernateTransactionManager.doBegin(HibernateTransactionManager.java:382)
	org.springframework.transaction.support.AbstractPlatformTransactionManager.getTransaction(AbstractPlatformTransactionManager.java:281)
	org.springframework.transaction.interceptor.TransactionAspectSupport.createTransactionIfNecessary(TransactionAspectSupport.java:217)
	org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:89)
	org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:144)
	org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:174)
	$Proxy5.searchProjects(Unknown Source)
	com.taiji.bms.web.action.project.SearchProjectAction.search(SearchProjectAction.java:63)
	sun.reflect.GeneratedMethodAccessor131.invoke(Unknown Source)
	sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
	java.lang.reflect.Method.invoke(Method.java:324)
	org.apache.struts.actions.DispatchAction.dispatchMethod(DispatchAction.java:274)
	org.apache.struts.actions.DispatchAction.execute(DispatchAction.java:194)
	org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:419)
	org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:224)
	org.apache.struts.action.ActionServlet.process(ActionServlet.java:1194)
	org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:414)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:689)
	javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
	com.taiji.bms.web.filter.SsoFilter.doFilter(SsoFilter.java:64)
	org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:75)
	org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)
	org.springframework.orm.hibernate3.support.OpenSessionInViewFilter.doFilterInternal(OpenSessionInViewFilter.java:174)
	org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76)


note The full stack trace of the root cause is available in the Apache Tomcat/5.0.28 logs.

我的理解：
我在spring配置文件里写到：

	<bean id="transactionManager" class="org.springframework.orm.hibernate3.HibernateTransactionManager">
		<property name="sessionFactory">
			<ref bean="uapSessionFactory" />
		</property>
	</bean>
	<bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
		<property name="dataSource">
			<ref bean="uapDataSource" />
		</property>
	</bean>
	<bean id="accountDao" class="com.taiji.uap.dao.hbm.AccountDaoHbm">
		<property name="sessionFactory">
			<ref bean="uapSessionFactory" />
		</property>
		<property name="jdbcTemplate">
			<ref bean="jdbcTemplate" />
		</property>
	</bean>

这样导致dao中既有hibernate的事务管理，又有数据源的事务管理，才出现上面的错误，我后来改为：

	<bean id="transactionManager" class="org.springframework.orm.hibernate3.HibernateTransactionManager">
		<property name="sessionFactory">
			<ref bean="uapSessionFactory" />
		</property>
	</bean>
	<bean id="accountDao" class="com.taiji.uap.dao.hbm.AccountDaoHbm">
		<property name="sessionFactory">
			<ref bean="uapSessionFactory" />
		</property>
	</bean>

这样就可以了

我的理解对么？谁对hibernate和数据源的事务处理有深入了解，请详细说明一下

有人了解么？