function newImage(arg) {
	if (document.images) {
		rslt = new Image();
		rslt.src = arg;
		return rslt;
	}
}
function changeImagesArray(array) {
	if (preloadFlag == true) {
		var d = document; var img;
		for (var i=0; i<array.length; i+=2) {
			img = null; var n = array[i];
			if (d.images) {img = d.images[n];}
			if (!img && d.getElementById) {img = d.getElementById(n);}
			if (img) {img.src = array[i+1];}
		}
	}
}
function changeImages() {
	changeImagesArray(changeImages.arguments);
}

var preloadFlag = false;
function preloadImages() {
	if (document.images) {
		pre_certifications_ro = newImage('images/certifications_ro.jpg');
		pre_join_ro = newImage('images/join_ro.jpg');
		pre_industry_ro = newImage('images/industry_ro.jpg');
		pre_support_ro = newImage('images/support_ro.jpg');
		pre_news_ro = newImage('images/news_ro.jpg');
		preloadFlag = true;
	}
}


sfHover = function() {
	var sfEls = document.getElementById("mainNav").getElementsByTagName("LI");
	for (var i=0; i<sfEls.length; i++) {
		sfEls[i].onmouseover=function() {
			this.className+=" sfhover";
		}
		sfEls[i].onmouseout=function() {
			this.className=this.className.replace(new RegExp(" sfhover\\b"), "");
		}
	}
}
if (window.attachEvent) window.attachEvent("onload", sfHover);