var preloaded = false;
function preloadImages() {
	if (document.images) {
		Button_01_over = new Image();
		Button_02_over = new Image();
		Button_03_over = new Image();
		Button_04_over = new Image();
		Button_05_over = new Image();
		Button_06_over = new Image();
		
		Button_01_over.src = "/images/Button_01-over.png";
		Button_02_over.src = "/images/Button_02-over.png";
		Button_03_over.src = "/images/Button_03-over.png";
		Button_04_over.src = "/images/Button_04-over.png";
		Button_05_over.src = "/images/Button_05-over.png";
		Button_06_over.src = "/images/Button_06-over.png";
		preloaded = true;
	}
}

function changeImage(imgName, imgSrc) {
	if (document.images && (preloaded == true)) {
		document[imgName].src = imgSrc;
	}
}