recent_browser = (((navigator.appName == "Netscape") && (parseInt(navigator.appVersion) >= 3 )) || ((navigator.appName == "Microsoft Internet Explorer") && (parseInt(navigator.appVersion) >= 4 )))
  if (recent_browser) {
   menu_rap1on = new Image();
   menu_rap1on.src ="graf/presenta_on.jpg";
   menu_rap1off = new Image();
   menu_rap1off.src = "graf/presenta_off.jpg";

   menu_rap2on = new Image();
   menu_rap2on.src = "graf/monumentos_on.jpg";
   menu_rap2off = new Image();
   menu_rap2off.src = "graf/monumentos_off.jpg";

   menu_rap3on = new Image();
   menu_rap3on.src = "graf/historia_on.jpg";
   menu_rap3off = new Image ();
   menu_rap3off.src = "graf/historia_off.jpg";

   menu_rap4on = new Image();
   menu_rap4on.src = "graf/habla_on.jpg";
   menu_rap4off = new Image();
   menu_rap4off.src = "graf/habla_off.jpg";
   
   menu_rap5on = new Image();
   menu_rap5on.src = "graf/servicios_on.jpg";
   menu_rap5off = new Image();
   menu_rap5off.src = "graf/servicios_off.jpg";
   
   menu_rap6on = new Image();
   menu_rap6on.src = "graf/enlaces_on.jpg";
   menu_rap6off = new Image();
   menu_rap6off.src = "graf/enlaces_off.jpg";
   
   menu_rap7on = new Image();
   menu_rap7on.src = "graf/acerca_on.jpg";
   menu_rap7off = new Image();
   menu_rap7off.src = "graf/acerca_off.jpg";

   menu_rap8on = new Image();
   menu_rap8on.src = "graf/visitas_on.jpg";
   menu_rap8off = new Image();
   menu_rap8off.src = "graf/visitas_off.jpg";

   menu_rap9on = new Image();
   menu_rap9on.src = "graf/escribe_on.gif";
   menu_rap9off = new Image();
   menu_rap9off.src = "graf/escribe_off.gif";
   }

function img_act(imgName)  {
   if (recent_browser)   {
   imgOn = eval(imgName + "on.src");
   document [imgName].src = imgOn;
   }
}

function img_inact(imgName)   {
   if (recent_browser) {
   imgOff = eval(imgName + "off.src");
   document [imgName].src = imgOff;
   }
}