function preloadImages() {
	if (document.images) {
		over1 = newImage("/images/by-nc-nd_over.png");
		over2 = newImage("/images/by-nc-sa_over.png");
		over3 = newImage("/images/by-sa_over.png");
		over4 = newImage("/images/pd_over.png");
		over5 = newImage("/images/by-nc_over.png");
		over6 = newImage("/images/by_over.png");
	}
}

function newImage(imgSrc){
	var imgName = new Image();
	imgName.src = imgSrc;
	return imgName;
}