function menu_hover(hover_element) {
	var imgsrc, elem, sar;
	elem = document.getElementById(hover_element);
	imgsrc = elem.src;
	sar = imgsrc.split("/");
	sar.reverse();
	if (sar[0].substr(0,2) == "l_") {
		elem.src = imgsrc.substr(0,imgsrc.length-sar[0].length) + sar[0].substr(2,sar[0].length-2)
	} else {
		elem.src = imgsrc.substr(0,imgsrc.length-sar[0].length) + "l_" + sar[0]
	}
}