browserName = navigator.appName;
  browserVer = parseInt(navigator.appVersion);

  if ((browserName == "Netscape" && browserVer >= 3) || browserVer >= 4) 
    versao ="n3";
  else 
    versao = "n2";
  
  if (versao == "n3") {

    menu1 = new Image;
    menu1.src = "images/menu1.png";
    menu1o = new Image;
    menu1o.src = "images/menu1o.png";
  
    menu2 = new Image;
    menu2.src = "images/menu2.png";
    menu2o = new Image;
    menu2o.src = "images/menu2o.png";

    menu3 = new Image;
    menu3.src = "images/menu3.png";
    menu3o = new Image;
    menu3o.src = "images/menu3o.png";

    menu4 = new Image;
    menu4.src = "images/menu4.png";
    menu4o = new Image;
    menu4o.src = "images/menu4o.png";
}

function op(Name,Img) {
	if (versao == "n3")
		document.images[Name].src = eval(Img + ".src")
}