如果条件添加链接magento?

My xml code:

我的xml代码:

<customer_account>
    <reference name="example_link">
        <action method="addLink" module="example" ifconfig="example/general/enable"><name>my_review</name><path>example/account/list/</path><label>My Review</label></action>
    </reference>
</customer_account>
<customer_account>