function preloadImages() {

var home = new Image();
home.src = "images/buttons/home_up.jpg";
var homedown = new Image();
homedown.src = "images/buttons/home_down.jpg";
var ab = new Image();
ab.src = "images/buttons/aboutus_up.jpg";
var abdown = new Image();
abdown.src = "images/buttons/aboutus_down.jpg";
var con = new Image();
con.src = "images/buttons/contactus_up.jpg";
var condown = new Image();
condown.src = "images/buttons/contactus_down.jpg";
var t = new Image();
t.src = "images/buttons/testimonials_up.jpg";
var tdown = new Image();
tdown.src = "images/buttons/testimonials_down.jpg";
var te = new Image();
te.src = "images/buttons/gallery_up.jpg";
var gdown = new Image();
gdown.src = "images/buttons/gallery_down.jpg";
} // end preload images

function swapButtons(obj, type) {
	if (type == "normal") {
		obj.src="images/buttons/" + obj.name + ".jpg";
	} else {
		obj.src="images/buttons/" + obj.name + "_" + type + ".jpg";
	} // end if  block
} // end swapButtons