function initialize () {
	var file = '';
	for (var i = 1; i <= 6; i++) {
		file = "img/nav" + i + ".gif";
		preload(file);
		file = "img/nav" + i + "_over.gif";
		preload(file);
	}
}
function preload () {
	if (!document.images) return;
	var ar = new Array();
	var arguments = preload.arguments;
	for (var i = 0; i < arguments.length; i++) {
		ar[i] = new Image();
		ar[i].src = arguments[i];
	}
}
function swap (obj,name,opt) {
	if (opt) obj.src = "img/" + name + "_over.gif";
	else obj.src = "img/" + name + ".gif";
}