// template includes

// main navigation rollovers
var W3CDOM = (document.createElement && document.getElementsByTagName);

// store pre-loaded images into two arrays
var mouseOvers = new Array();
var mouseOuts = new Array();

window.onload = init;

function init() {
	if (!W3CDOM) return; // end function if W3C DOM is not supported
	var nav = document.getElementById('main_nav');
	var imgs = nav.getElementsByTagName('img');
	for (var i=0; i<imgs.length; i++) {
		imgs[i].onmouseover = mouseGoesOver;
		imgs[i].onmouseout = mouseGoesOut;
		var suffix = imgs[i].src.substring(imgs[i].src.lastIndexOf('.'));
		mouseOuts[i] = new Image();
		mouseOuts[i].src = imgs[i].src;
		mouseOvers[i] = new Image();
		mouseOvers[i].src = imgs[i].src.substring(0,imgs[i].src.lastIndexOf('.')) + "-on" + suffix;
		imgs[i].number = i;
	}
}

function mouseGoesOver() {
	this.src = mouseOvers[this.number].src;
}

function mouseGoesOut() {
	this.src = mouseOuts[this.number].src;
}