bName = navigator.appName;
bVer = parseInt(navigator.appVersion);
bReady = false;

if (bName == "Netscape" && bVer >= 3) bReady = true;
else if (bName == "Microsoft Internet Explorer" && bVer >= 4) bReady = true;
  
function Button(norm_src,sel_src)
 {
  if (bReady)
  {
   this.norm=new Image();
   this.sel=new Image();
   this.norm.src=norm_src;
   this.sel.src=sel_src;
  }
 }

function overpic(Image_Name) {
  if (bReady) {
	document[Image_Name].src = eval(Image_Name+".sel.src");
   }
 }


function leftpic(Image_Name) {
  if (bReady) {
    document[Image_Name].src = eval(Image_Name+".norm.src");
  }
 }