function nav_mouseover(id,dir)
{
	var idnr, splited, file, part, i;
	splited = id.split("-");
	idnr = splited[1];
	idnr = parseInt(idnr);
	part = new Array("mouseover-left", "mouseover-center", "mouseover-right");
	for(i = -1; i <= 1; i++)
	{
		file = new Image();
		file.src = dir + "img/mainnav/" + part[i + 1] + ".gif";
		id = idnr + i;
		id = "mainnav-" + id;
		window.document.images[id].src = file.src;
	}
}

function nav_mouseout(id,dir)
{
	var idnr, splited, file, i;
	splited = id.split("-");
	idnr = splited[1];
	idnr = parseInt(idnr);
	file = new Image();
	file.src = dir + "img/mainnav/mouseout.gif";
	for(i = -1; i <= 1; i++)
	{
		id = idnr + i;
		id = "mainnav-" + id;
		window.document.images[id].src = file.src;
	}
}