spring与hibernate整合,如何配置与多个数据库连接的事务?

现有两个不同的数据库,一个为sql2000,一个为oracle9i。问题：
1.如果两个数据库中有名字结构相同的两个表，如都为login，spring该如何配置对两个数据库该表的操作到一个事务中？hibernate是否可以用同一个pojo类和xml配置文件。
2.如果是对不同的表操作，又该如何配置？


对单个数据库的配置如下：
applicationContext.xml
------------------------------
<?xml version="1.0" encoding="UTF-8"?>

<!--
- Application context definition for JPetStore's business layer.
- Contains bean references to the transaction manager and to the DAOs in
- dataAccessContext-local/jta.xml (see web.xml's "contextConfigLocation").
-->
<beans xmlns="http://www.springframework.org/schema/beans"
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.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">


<!--
配置数据源
注意: 用org.apache.commons.dbcp.BasicDataSource, 要引入 apache commons
的commons-collections-3.1.jar, commons-dbcp-1.2.1.jar, commons-pool-1.2.jar三个包
-->
<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close">
<property name="driverClassName">
<value>net.sourceforge.jtds.jdbc.Driver</value>
</property>
<property name="url">
<value>jdbc:jtds:sqlserver://psw3000:1433;DatabaseName=netstore</value>
</property>
<property name="username">
<value>nsrsccdqy</value>
</property>
<property name="password">
<value>35547118</value>
</property>
</bean>

<!-- 配置sessionFactory -->
<bean id="sessionFactory"
class="org.springframework.orm.hibernate3.LocalSessionFactoryBean">
<property name="dataSource">
<ref local="dataSource" />
</property>
<property name="mappingResources">
<list>
<value>gov/cd12366/bridge/domain/Login.hbm.xml</value>
</list>
</property>
<property name="hibernateProperties">
<props>
<prop key="hibernate.dialect">
org.hibernate.dialect.SQLServerDialect
</prop>
<prop key="hibernate.show_sql">true</prop>
</props>
</property>
</bean>

<!-- 配置transactionManager -->
<bean id="transactionManager"
class="org.springframework.orm.hibernate3.HibernateTransactionManager">
<property name="sessionFactory">
<ref local="sessionFactory" />
</property>
</bean>

<bean id="LoginDAO" class="gov.cd12366.bridge.persistence.dao.LoginDAO">
<property name="sessionFactory">
<ref local="sessionFactory" />
</property>
</bean>
<!-- 配置事务代理,对LoginDAO的insert,和get方法进行不同的事务配置 -->
<bean id="LoginDAOProxy"
class="org.springframework.transaction.interceptor.TransactionProxyFactoryBean">
<property name="transactionManager">
<ref bean="transactionManager" />
</property>
<property name="target">
<ref local="LoginDAO" />
</property>
<property name="transactionAttributes">
<props>
<prop key="insert*">PROPAGATION_REQUIRED</prop>
<prop key="get*">PROPAGATION_REQUIRED,readOnly</prop>
</props>
</property>
</bean>

</beans>