browser_name = navigator.appName;
browser_version = parseFloat(navigator.appVersion);

if(browser_name == "Netscape" && browser_version >= 3.0) {
  version = "ok";
}
else if (browser_name == "Microsoft Internet Explorer" && browser_version >= 3.0) {
  version = "ok";
}
else if (browser_name == "Opera" && browser_version >= 6.0) {
  version = "ok";
}
else {
  version = "bad";
}


if (version == "ok") {

 firmaon = new Image();
 firmaon.src="images/index/firma1.gif";
 firmaoff = new Image();
 firmaoff.src="images/index/firma.gif";

 stacjeon = new Image();
 stacjeon.src="images/index/stacje1.gif";
 stacjeoff = new Image();
 stacjeoff.src="images/index/stacje.gif";

 kontakton = new Image();
 kontakton.src="images/index/kontakt1.gif";
 kontaktoff = new Image();
 kontaktoff.src="images/index/kontakt.gif";

 ofertaon = new Image();
 ofertaon.src="images/index/oferta1.gif";
 ofertaoff = new Image();
 ofertaoff.src="images/index/oferta.gif";
 
 formularzon = new Image();
 formularzon.src="images/index/formularz1.gif";
 formularzoff = new Image();
 formularzoff.src="images/index/formularz.gif";
 
 aktualnoscion = new Image();
 aktualnoscion.src="images/index/aktualnosci1.gif";
 aktualnoscioff = new Image();
 aktualnoscioff.src="images/index/aktualnosci.gif";
 
 referencjeon = new Image();
 referencjeon.src="images/index/referencje1.gif";
 referencjeoff = new Image();
 referencjeoff.src="images/index/referencje.gif";

 

 

 function imgact(imgName) {
   if (version == "ok")
   {
     imgOn = eval(imgName + "on.src");
     document [imgName].src = imgOn;
   }
 }


 function imgnoact(imgName) {
   if (version == "ok")
   {
     imgOff = eval(imgName + "off.src");
     document [imgName].src = imgOff;
   }
 }

}