function over(obj, url) {
	obj.style.backgroundImage = "url("+url+")";
}

function unover(obj, url) {
	if(url == "none") {
		obj.style.backgroundImage = url;
	} else {
		obj.style.backgroundImage = "url("+url+")";
	}
}

function newImg(loc){
	if(document.images){
		img = new Image;
		img.src = loc;
		return img;
	}
}