try {
    var jqueryLoaded = jQuery;
    jqueryLoaded = true;
} catch (err) {
    var jqueryLoaded = false;
}
if (!jqueryLoaded) {
    var head = document.getElementsByTagName('head')[0];
    var script = document.createElement('script');
    script.type = 'text/javascript';
    script.src = 'http://ajax.googleapis.com/ajax/libs/jquery/1.4.4/jquery.min.js';
    head.appendChild(script);
}

$jqr = jQuery.noConflict();