I am trying to grab information from an external xml with the following code. It only worked when I uploaded same file to my servers. Why cant I grab information from an external url?

<script language="javascript">
// This script uses jQuery to retrieve the news XML file and display the contents
$(document).ready(function(){

	$.ajax({
	    type: "GET",
		url: "www.simplyprofound.com/samples/xml_jquery/sample.xml",
		dataType: "xml",
		success: function(xml) {
			$(xml).find('item').each(function(){
				var title = $(this).find('title').text();
				var source = $(this).find('source').text();
				var description = $(this).find('description').text();
				$('<div class="news_title"></div>').html(title).appendTo('#news_wrap');
				$('<div class="news_source"></div>').html(source).appendTo('#news_wrap');
				$('<div class="news_description"></div>').html(description).appendTo('#news_wrap');
			});
		}
	});
});
</script>