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

function changeImage(name,patch) {
	if (document.images && (preloadFlag == true)) {
		document[name].src = patch;
	}
}

var preloadFlag = false;
function preloadImages() {
	if (document.images) {
		i1_over = newImage("img/4-1-over.gif");
		i2_over = newImage("img/4-3-over.gif");
		i3_over = newImage("img/3-1-over.gif");
		i4_over = newImage("img/3-2-over.gif");
		i5_over = newImage("img/3-3-over.gif");
		preloadFlag = true;
	}
}