var ns4 = (document.layers)? true:false;   			//NS 4 
var ie4 = (document.all)? true:false;   				//IE 4 
var dom = (document.getElementById)? true:false;   //DOM
var PreloadFlag = false;

function PreloadImg()
	{
	var Args = PreloadImg.arguments;
	var MyImages = new Array();
	if (document.images)
		{
		for(var i=0; i<Args.length; i++)
			{
			MyImages[i]= new Image();
			MyImages[i].src = Args[i];
			}
		PreloadFlag = true;
		}
	}

function ChangeImg()
	{
	var Args = ChangeImg.arguments;
	var ImgName;
	for(var i=0; i<Args.length; i+=2)
		{
		ImgName = Args[i];
		//alert(document.images[ImgName].src);
		document.images[ImgName].src = Args[i+1];
		}
	}

	function ImgSwap(imgName, imgSrc)
{
  var appVer=parseInt(navigator.appVersion);
  var isNC=false,isN6=false,isIE=false;
  if (document.all && appVer >= 4) isIE=true; else
    if (document.getElementById && appVer > 4) isN6=true; else
      if (document.layers && appVer >= 4) isNC=true;
  if (isNC||isN6||isIE)
  {
    if (document.images)
    {
      var img = document.images[imgName];
      if (!img) img = ImgFing(document, imgName);
      if (img) img.src = imgSrc;
    }
  }
}

function ImgFing(doc, imgName)
{
  for (var i=0; i < doc.layers.length; i++)
  {
    var img = doc.layers[i].document.images[imgName];
    if (!img) img = ImgFing(doc.layers[i], imgName);
    if (img) return img;
  }
  return null;
}