Error when loading jQuery UI library from a Firefox extension

Hi all, I've a problem when I try to load jQuery UI from a Firefox extension.

I can successfully load jQuery, but when I add jQuery UI library I have an error.

That's the code I'm using to load it:

window.addEventListener("load", function loadme(){
	window.removeEventListener("load", loadme, false);
	
	myext.loadLibraries(myext);
}, false);

var myext = {
    loadLibraries: function(context) {
            //load jQuery
            var loader = Components.classes["@mozilla.org/moz/jssubscript-loader;1"]
                                                         .getService(Components.interfaces.mozIJSSubScriptLoader);
            loader.loadSubScript("chrome://myext/jquery-1.9.1.js",context);
            var jQuery = window.jQuery.noConflict(true);
           
        if( typeof(jQuery.fn._init) == 'undefined') { jQuery.fn._init = jQuery.fn.init; }
       
        var $ = function(selector,context){ return new jQuery.fn.init(selector,myext.doc); };
        $.fn = $.prototype = jQuery.fn;
       
        myext.jQuery = jQuery;
        myext.$ = $;

        loader.loadSubScript("chrome://myext/jquery-ui-1.10.0.custom.js", context);
        loader.loadSubScript("chrome://myext/jquery.tipsy.js", jQuery);
   
    }
}

That's the error I see:

Errore: TypeError: tmp is null

File sorgente: chrome://myext/content/lib/jquery-1.9.1.js

Riga: 6501

I'm currently testing it with Firefox 17.0.1, jQuery 1.9.1 and jQuery UI 1.10.0 under Windows XP.

I don't know if someone can help me to understand if it's a jQuery UI's bug, or a problem in the way I'm following to load it.

Thanks in advance and best regards,

liv913