MSFPhover = 
  (((navigator.appName == "Netscape") && 
  (parseInt(navigator.appVersion) >= 3 )) || 
  ((navigator.appName == "Microsoft Internet Explorer") && 
  (parseInt(navigator.appVersion) >= 4 ))); 

function MSFPpreload(img)
{
	var a = new Image();
	a.src = img;
	return a;
}
if (MSFPhover) 
{ 
	var baseDir = "/images/";
	MSFPnav1n = MSFPpreload(baseDir + "historia.gif"); 
	MSFPnav1h = MSFPpreload(baseDir + "historiaS.gif"); 
	MSFPnav2n = MSFPpreload(baseDir + "reprod.gif"); 
	MSFPnav2h = MSFPpreload(baseDir + "reprodS.gif"); 
	MSFPnav3n = MSFPpreload(baseDir + "servicios.gif"); 
	MSFPnav3h = MSFPpreload(baseDir + "serviciosS.gif"); 
	MSFPnav4n = MSFPpreload(baseDir + "contacto.gif"); 
	MSFPnav4h = MSFPpreload(baseDir + "contactoS.gif"); 
	MSFPnav5n = MSFPpreload(baseDir + "inicio.gif"); 
	MSFPnav5h = MSFPpreload(baseDir + "inicioS.gif"); 
	MSFPnav6n = MSFPpreload(baseDir + "logros.gif"); 
	MSFPnav6h = MSFPpreload(baseDir + "logrosS.gif"); 
	MSFPnav7n = MSFPpreload(baseDir + "camadas.gif"); 
	MSFPnav7h = MSFPpreload(baseDir + "camadasS.gif"); 
	MSFPnav8n = MSFPpreload(baseDir + "machos.gif"); 
	MSFPnav8h = MSFPpreload(baseDir + "machosS.gif"); 
	MSFPnav9n = MSFPpreload(baseDir + "hembras.gif"); 
	MSFPnav9h = MSFPpreload(baseDir + "hembrasS.gif"); 
	MSFPnav10n = MSFPpreload(baseDir + "temasint.gif"); 
	MSFPnav10h = MSFPpreload(baseDir + "temasintS.gif"); 
	MSFPnav11n = MSFPpreload(baseDir + "enventa.gif"); 
	MSFPnav11h = MSFPpreload(baseDir + "enventaS.gif"); 
	MSFPnav12n = MSFPpreload(baseDir + "noticia.gif"); 
	MSFPnav12h = MSFPpreload(baseDir + "noticiaS.gif"); 
	MSFPnav13n = MSFPpreload(baseDir + "galeria.gif"); 
	MSFPnav13h = MSFPpreload(baseDir + "galeriaS.gif"); 
}