function preloadImages(the_images_array) {
   for(var loop = 0; loop < the_images_array.length; loop++)	
   {
 	var an_image = new Image();
	an_image.src = the_images_array[loop];
   }
}

startList = function() {
if (document.all&&document.getElementById) {
	navRoot = document.getElementById("menuNavLeft");
	for (i=0; i<navRoot.childNodes.length; i++) {
		node = navRoot.childNodes[i];
		if (node.nodeName=="LI") {
			node.onmouseover=function() {
				this.className+=" over";
			}
			node.onmouseout=function() {
				this.className=this.className.replace(" over", "");
   			}
  		}
	}
}
}
window.onload=startList;

function enPreload()
{
   var menu_images = new Array(
		'/en/resource/image/menu_about_us_f2.gif',
        '/en/resource/image/menu_contact_us_f2.gif',
        '/en/resource/image/menu_home_f2.gif',
        '/en/resource/image/menu_portfolio_f2.gif',
        '/en/resource/image/menu_request_a_trial_f2.gif');
	preloadImages(menu_images);
}