//________________PRELOAD IMMAGINI__________________
	function bannerCambia(url){
		var a;
		var tot = 12;
		a = 1+Math.round(Math.random()*tot); 

		//document.images['alto'].src= "http://tuttorock.altervista.org/img/img_6.jpg";
		//document.images['alto'].src= "http://massysp.altervista.org/img/img_5.jpg";
	 }