confirn in link on overlay lists
Some code:

$option_delete = array(
        'attributes' =&gt; array(
            'onclick' =&gt; "return confirm('Delete order?');",
            'class' =&gt; "delete"
        )
    );


link:

l('delete', 'admin/orders/categories/'.$node-&gt;id.'/'.$page, $option_delete),


this link is showing up in list on administration overlay.