function newImage(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) {
		menu_home_over = newImage("images/menu_home-over.gif");
		menu_services_over = newImage("images/menu_services-over.gif");
		menu_education__over = newImage("images/menu_education--over.gif");
		menu_about_over = newImage("images/menu_about-over.gif");
		menu_contact_over = newImage("images/menu_contact-over.gif");
		menu_specials_over = newImage("images/menu_specials-over.gif");
                menu_links_over = newImage("images/menu_specials-over.gif");
		menu_featured_over = newImage("images/menu_specials-over.gif");
		preloadFlag = true;
	}
};

<!-- Hide from old browsers

var imagenumber = 8;
var randomnumber = Math.random() ;
var rand1 = Math.round( (imagenumber-1) * randomnumber) + 1 ;
images = new Array
images[1] = "images/banner_01.jpg"
images[2] = "images/banner_02.jpg"
images[3] = "images/banner_03.jpg"
images[4] = "images/banner_04.jpg"
images[5] = "images/banner_05.jpg"
images[6] = "images/banner_06.jpg"
images[7] = "images/banner_07.jpg"
images[8] = "images/banner_08.jpg"

var image = images[rand1]
// -- End Hiding Here -->