问spring hibernate hibernate.connection.provider_class未被调用

EN

<spring:bean id="sessionFactory"
            class="org.springframework.orm.hibernate3.annotation.AnnotationSessionFactoryBean">
            <spring:property name="dataSource" ref="dataSource" />
            <spring:property name="packagesToScan" value="${hibernate.packagesToScan}" />
            <spring:property name="eventListeners">
                <spring:map>
                    <spring:entry key="pre-insert">
                        <spring:bean
                            class="com.myapp.listener.PreInsertOrUpdateEventListener"
                            id="preInsertOrUpdateEventListener" />
                    </spring:entry>
                    <spring:entry key="pre-update">
                        <spring:bean
                            class="com.myapp.listener.PreInsertOrUpdateEventListener"
                            id="preInsertOrUpdateEventListener" />
                    </spring:entry>
                </spring:map>
            </spring:property>
            <spring:property name="hibernateProperties">
                <spring:props>
                    <spring:prop key="hibernate.dialect">${hibernate.dialect}</spring:prop>
                    <spring:prop key="hibernate.show_sql">${hibernate.show_sql}</spring:prop>
                    <spring:prop key="hibernate.hbm2ddl.auto">${hibernate.hbm2ddl.auto}
                    </spring:prop>
                    <spring:prop key="hibernate.temp.use_jdbc_metadata_defaults">${hibernate.temp.use_jdbc_metadata_defaults}
                    </spring:prop>
                    <spring:prop key="hibernate.connection.provider_class">${hibernate.connection.provider_class}
                    </spring:prop>
                    <spring:prop key="hibernate.dbcp.initialSize">${hibernate.dbcp.initialSize}
                    </spring:prop>
                    <spring:prop key="hibernate.dbcp.maxActive">${hibernate.dbcp.maxActive}
                    </spring:prop>
                    <spring:prop key="hibernate.dbcp.maxIdle">${hibernate.dbcp.maxIdle}
                    </spring:prop>
                    <spring:prop key="hibernate.dbcp.minIdle">${hibernate.dbcp.minIdle}
                    </spring:prop>
                </spring:props>
            </spring:property>
        </spring:bean>

<spring:bean id="dataSource" name="dataSource"
            class="org.apache.commons.dbcp.BasicDataSource">
            <spring:property name="driverClassName" value="${db.driverClassName}" />
            <spring:property name="url" value="${db.url}" />
            <spring:property name="username" value="${db.username}" />
            <spring:property name="password" value="${db.password}" />
        </spring:bean>