// check the browser version
 browserName = navigator.appName;
 browserVer = parseInt(navigator.appVersion);
 if (browserName == "Netscape" && browserVer >= 3)
	version ="n3";
	else
	if ((browserName == "Microsoft Internet Explorer") && (browserVer >=4))
		version= "ie4";
		else
		version ="x";
//activate button
function activ(button){
   if (version != "x"){
   picOn = eval(button + "On.src");
   document [button].src = picOn;
  					   	 }
					   }
//deactivate button
function passiv(button2){
   if ((version != "x") && (button2 != clicked)){
   picOff = eval(button2 + "Off.src");
   document [button2].src = picOff;
   					  }					  
						}