var timeout = false;

function rollOn(img){
	if (document.images) {
		document.menu_image.src = eval(img + ".src");
		timeout = true;
	}
}

function rollOff(img){
	if (document.images) {
		if (!img)
		{
			document.menu_image.src = unselected.src
		}
		else
		{
			setTimeout('update_menu(\'' + eval(img + ".src") + '\')', 2000);
		}
		timeout = false;
	}
}

function update_menu(img_src)
{
	if (!timeout)
	{
		document.menu_image.src = img_src;
	}
}