function navOut(id)
{
	document.images[id].src = "media/nav_" + id + "_" + ((currentOn != id) ? "off" : "on") + ".gif";
}
function navOver(id)
{
	document.images[id].src = "media/nav_" + id + "_over.gif";
}
function setOn(id)
{
	top.header.document.images['title'].src = "media/header_" + id + ".gif";
	var tmpId = currentOn;
	currentOn = id;
	navOut(tmpId);
}