EntityManager configuration in each DAO
@PersistenceContext
private EntityManager em;

<bean class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close"  id="dataSource">
    <property name="url" value="jdbc:mysql://localhost:3306/xxxxx"/>
    <property name="username" value="xxxx"/>
    <property name="password" value="xxxx"/>
    <property name="driverClassName" value="com.mysql.jdbc.Driver"/>
</bean>

<bean class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean" id="entityManagerFactory">
    <property name="dataSource" ref="dataSource"/>
    <property name="jpaVendorAdapter" ref="jpaVendorAdapter"/>
    <property name="jpaDialect" ref="jpaDialect"/>
</bean>

<bean class="org.springframework.orm.jpa.JpaTransactionManager" id="transactionManager">
    <property name="entityManagerFactory" ref="entityManagerFactory"/>
    <property name="jpaDialect" ref="jpaDialect"/>
</bean>

<bean id="jpaVendorAdapter" class="org.springframework.orm.jpa.vendor.EclipseLinkJpaVendorAdapter" >
    <property name="showSql" value="true"/>
    <property name="generateDdl" value="true" />
</bean>

<bean id="jpaDialect" class="org.springframework.orm.jpa.vendor.EclipseLinkJpaDialect"/>

<persistence-unit name="xxxxx" transaction-type="RESOURCE_LOCAL">
<provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>
<-- class mappings -->
</persistence-unit>

<property name="jpaDialect">
    <bean class="com.foo.util.persistence.EclipseLinkExtendedJpaDialect" />
</property>