SO jQuery Fiddle

Test Fiddle mainly for SO Questions jQuery 1.4.3, UI 1.8.5

HTML

<link rel="stylesheet" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.5/themes/ui-lightness/jquery-ui.css">
<p>Date: <input type="hidden" id="datepicker"></p>

JavaScript

$( "#datepicker" ).datepicker({
    showOn: "both",
    buttonImage: "http://jqueryui.com/demos/datepicker/images/calendar.gif",
    buttonImageOnly: true
});