function plato(arg) {
	if (document.images) {
		rslt = new Image();
		rslt.src = arg;
		return rslt;
	}
}

function changeImages() {
	if (document.images && (preloadFlag == true)) {
		for (var i=0; i<changeImages.arguments.length; i+=2) 
		{
			document[changeImages.arguments[i]].src = changeImages.arguments[i+1];
		}
	}
}

var preloadFlag = false;
function preloadImages() {
	if (document.images) 
	{
	  var imgFiles = preloadImages.arguments;
      for (var i=0; i<imgFiles.length; i+=2) 
      {
        eval(imgFiles[i]+' = plato(imgFiles[i+1])');
        eval(imgFiles[i]+'.src = "'+imgFiles[i+1]+'"');
      }
		preloadFlag = true;
	}
}

preloadImages(
	'contact','ns_contact_us_on.gif',
	'contact','Email_Friend_roll.gif',
	'downloads','ns_downloads_on.gif',
	'purchase','ns_purchase_on.gif',
	'request','ns_request_info_on.gif');