var aOnImgs = new Array();
var aOffImgs = new Array();

function fnRollOn() {
	//alert(this.getAttribute('name').match('navimg_([0-9])')[1]);
	var iID = this.getAttribute('id').match('navimg_([0-9])')[1];
	//this.setAttribute('src', aOnImgs[iID].src);
	//this.src = aOnImgs[iID].src
	document.images[this.id].src = aOnImgs[iID].src;
}

function fnRollOff() {
	//alert(this.getAttribute('id').match('navimg_([0-9])')[1]);
	var iID = this.getAttribute('id').match('navimg_([0-9])')[1];
	//this.setAttribute('src', aOffImgs[iID].src);
	//this.src = aOffImgs[iID].src
	document.images[this.id].src = aOffImgs[iID].src;
}

function fnInitMainMenu() {
	var elMainMenu = document.getElementById('main_nav');
	var aImgs = elMainMenu.getElementsByTagName('img');
	for(var i=0; i<aImgs.length; i++) {
		aOffImgs[i] = new Image();
		aOffImgs[i].src = aImgs[i].getAttribute('src');

		aOnImgs[i] = new Image();
		aOnImgs[i].src = aImgs[i].getAttribute('src').replace('moff','mon');
		
		aImgs[i].id = 'navimg_' + i;
		aImgs[i].onmouseover = fnRollOn;
		aImgs[i].onmouseout = fnRollOff;
		
		//alert('aOffImgs ' + i + ' = ' + aOffImgs[i].src + 'aOnImgs ' + i + ' = ' + aOnImgs[i].src);
	}
}

if(window.addEventListener) {
	window.addEventListener('load', fnInitMainMenu, false);
}

if(window.attachEvent) {
	window.attachEvent('onload', fnInitMainMenu);
}