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) {
		sb1_over = newImage("img/otano/ob1-over.gif");
		sb1_down = newImage("img/otano/ob1-down.gif");
		sb2_over = newImage("img/otano/ob2-over.gif");
		sb2_down = newImage("img/otano/ob2-down.gif");
		
		return_over = newImage("img/otano/return-over.gif");
		return_down = newImage("img/otano/return-down.gif");
		
		buy_over = newImage("img/buy-over.gif");
		buy_down = newImage("img/buy-down.gif");
		
		toku_over = newImage("img/toku-over.gif");
		toku_down = newImage("img/toku-down.gif");
		
		header2 = newImage("img/header2.gif");
		bg_aya = newImage("img/bg_aya.gif");
		footer = newImage("img/footer.gif");
		
		size1_over = newImage("img/otano/size1-over.gif");
		size1_down = newImage("img/otano/size1-down.gif");
		size2_over = newImage("img/otano/size2-over.gif");
		size2_down = newImage("img/otano/size2-down.gif");
		size3_over = newImage("img/otano/size3-over.gif");
		size3_down = newImage("img/otano/size3-down.gif");
		
		
		
		
		preloadFlag = true;
	}
}