function menuHover(a) {
	var img = a.getElementsByTagName('IMG')[0];
	var slash = img.src.lastIndexOf('/') + 1;
	var path = img.src.substring(0, slash);
	var file = img.src.substring(slash);
	var dot = file.lastIndexOf('.');
	var ext = file.substring(dot);
	file = file.substring(0, dot);
	if(file.indexOf('_over') == -1) img.src = path + file + '_over' + ext;
}

function menuUnhover(a) {
	var img = a.getElementsByTagName('IMG')[0];
	var slash = img.src.lastIndexOf('/') + 1;
	var path = img.src.substring(0, slash);
	var file = img.src.substring(slash);
	var dot = file.lastIndexOf('.');
	var ext = file.substring(dot);
	file = file.substring(0, dot);
	if(file.indexOf('_over') != -1) img.src = path + file.replace('_over', '') + ext;
}