function newImage(arg) {
	if (document.images) {
		rslt = new Image();
		rslt.src = arg;
		return rslt;
	}
}

function changeImages() {
	if (document.images && (preloadFlag == true)) {
		for (var i=0; i<changeImages.arguments.length; i+=2) {
			document[changeImages.arguments[i]].src = changeImages.arguments[i+1];
		}
	}
}

var preloadFlag = false;
function preloadImages() {
	if (document.images) {
		reservation_over = newImage("images/reservation_over.gif");
		members_over = newImage("images/members_over.gif");
		news_over = newImage("images/news_over.gif");
		protocols_over = newImage("images/protocols_over.gif");
		proteomics_over = newImage("images/proteomics_over.gif");
		directions_over = newImage("images/directions_over.gif");
		preloadFlag = true;
	}
}