function popup(str,winName,larg,alt){
	var left = ((screen.width-larg)/2);
//	var top = ((screen.height-alt)/2);
	var top = 0;
	finestra = window.open(str,winName,"width=" + larg + ", height=" + alt + ", left=" + left + ",top=" + top + ", scrollbars, resizable" );
	finestra.focus();
}function virtual(str){
	finestra=window.open(str,"virtual","width=320, height=300 top=200 left=100")	
	finestra.focus();
}