XML parsing in jQuery - 3rd level nodes

I have an XML like this:

<?xml version="1.0"?>
<service>
    <name>My Element</name>
    <header>My Header</header>
    <sections>
        <section>
            <!-- Optional -->
            <subheader>Subheader 1</subheader>
            <description>Here goes the content</description>
        </section>
        <!-- Optional -->
        <section>
            <subheader>Subheader 2</subheader>
            <description>Here goes the content</description>
        </section>
    </sections>
</service>

And I am trying to read the values of the "subheader" and "description" element from each section. However I am unable to retrieve the values of these elements. Here is my code:

function getDescription(descriptor_url) {
        var descriptor_object = $.get(descriptor_url, function(descriptor_data, descriptor_status, descriptor_response) {
            $(descriptor_response.responseXML).each(function () {
                //this works fine
                var header = $(this).find('header').text();
            });
            $(descriptor_response.responseXML).find('sections').each(function() {
                // here is where the issue is
                $(this).find('section').each(function() {
                    var subheader = $(this).find('subheader').text;
                    alert(subheader);
                })
            })
        })
        .fail(function() { 
           response.value = "Something went wrong with the request.\n\nReason: " + descriptor_object.statusText;
        })
    }

I was thinking that $(this) is local to $.each loop but looks like i'm wrong. Can someone please help?

Thanks!