var nc      = !!(document.captureEvents && !document.documentElement);
var ie      = !!document.all;
var ie4     = !!(!document.documentElement && document.all);
var dom     = !!document.documentElement;
var nc6     = !!(dom && (!document.all));
var mac     = !!(navigator.userAgent.indexOf("Mac")!=-1);


var finestra = "";
function newWin(page,br,ho) {
    var scr     = (typeof arguments[3] != "undefined")? arguments[3] : "yes";
	  var ext     = (typeof arguments[4] != "undefined")? true : false;
    var largh   = screen.availWidth;
    var alt     = screen.availHeight;
    var winPosX = (largh/2) - br/2;
    var winPosY = (alt/2) - ho/2;

    if(!ie4 && finestra && !finestra.closed)
      finestra.location.href    = page;
    else 
      finestra = window.open(page,"","resizable=yes,scrollbars="+scr+",width="+br+",height="+ho);

    if(!ext)finestra.moveTo(winPosX,winPosY);
    if(!ext)finestra.resizeTo(br,ho);
    finestra.focus();
}