怎样在spring+jpa中配置多个persistence-unit

[joygarden]

比如persistence.xml中unit1 和unit2 在spring配置文件中应该怎样配置:

<?xml version="1.0" encoding="UTF-8"?>
<persistence xmlns="http://java.sun.com/xml/ns/persistence"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://java.sun.com/xml/ns/persistence
    http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd"
	version="1.0">

	<persistence-unit name="unit1"
		transaction-type="RESOURCE_LOCAL">
		<provider>org.hibernate.ejb.HibernatePersistence</provider>
		<class></class>
		<properties>
			<property name="hibernate.dialect"
				value="org.hibernate.dialect.Oracle10gDialect" />
			<property name="hibernate.connection.driver_class"
				value="oracle.jdbc.driver.OracleDriver" />
			<property name="hibernate.connection.url"
				value="jdbc:oracle:thin:@xxx.xxx.xxxx.xxxx:1521:xxx" />
			<property name="hibernate.connection.username"
				value="xxxx" />
			<property name="hibernate.connection.password"
				value="xxxx" />
		</properties>
	</persistence-unit>

	<persistence-unit name="unit2"
		transaction-type="RESOURCE_LOCAL">
		<provider>org.hibernate.ejb.HibernatePersistence</provider>
		
		<properties>
			<property name="hibernate.dialect"
				value="org.hibernate.dialect.Oracle10gDialect" />
			<property name="hibernate.connection.driver_class"
				value="oracle.jdbc.driver.OracleDriver" />
			
			<property name="hibernate.connection.url"
				value="jdbc:oracle:thin:@xxx.xxx.xxxx.xxxx:1521:xxx" />
			<property name="hibernate.connection.username"
				value="xxxx" />
			<property name="hibernate.connection.password"
				value="xxxx" />
			<property name="hibernate.show_sql" value="false" />
			<property name="hibernate.c3p0.timeout" value="50000" />
			<property name="hibernate.c3p0.idle_test_period"
				value="300" />
			<property name="hibernate.hbm2ddl.auto" value="true" />
			<property name="hibernate.default_schema" value="xxxx" />
		</properties>
	</persistence-unit>

</persistence>