XPathAPI - trouble with XPath to specific node index

Here’s my sample XML:

<?xml version="1.0" encoding="ISO-8859-1"?>

<xml>
    <media>
        <playlist>
            <clip>Sdfsdfadf</clip>
            <clip>asdfsdfsdf</clip>
            <clip>Sdfsdfadf</clip>
            <clip>asdfsdfsdf</clip>
            <clip>Sdfsdfadf</clip>
            <clip>asdfsdfsdf</clip>
            <clip>Sdfsdfadf</clip>
            <clip>asdfsdfsdf</clip>
        </playlist>
        <playlist>
            <clip>Sdfsdfadf</clip>
            <clip>asdfsdfsdf</clip>
            <clip>Sdfsdfadf</clip>
            <clip>asdfsdfsdf</clip>
            <clip>Sdfsdfadf</clip>
            <clip>asdfsdfsdf</clip>
            <clip>Sdfsdfadf</clip>
            <clip>asdfsdfsdf</clip>
            <clip>Sdfsdfadf</clip>
            <clip>asdfsdfsdf</clip>
            <clip>Sdfsdfadf</clip>
            <clip>asdfsdfsdf</clip>
        </playlist>
    </media>
</xml>

In the XML onLoad event handler, I have been trying to read in JUST the first node using both of these approaches:

var xPathTemp:String = "/xml/media/playlist[0]";
var xPathData:Object = XPathAPI.selectNodeList(xmlData.firstChild, xPathTemp);

// OR

var xPathTemp:String = "/xml/media/playlist[0]";
var xPathData:Object = XPathAPI.selectSingleNode(xmlData.firstChild, xPathTemp);

The first method returns nothing – it’s blank when I trace xPathData. The 2nd method returns null. What am I missing here? I ONLY ever want to get the first <playlist> node using XPathAPI.

Thanks,
IronChefMorimoto