function ImagePreload() {
  // set image list
  images = new Array();
  images[0]="/images/buttons/01r.gif";
  images[1]="/images/buttons/02r.gif";
  images[2]="/images/buttons/03r.gif";
  images[3]="/images/buttons/04r.gif";
  images[4]="/images/buttons/05r.gif";
  images[5]="/images/buttons/06r.gif";
  images[6]="/images/buttons/07r.gif";
  images[7]="/images/buttons/08r.gif";
  images[8]="/images/buttons/09r.gif";
  images[9]="/images/buttons/10r.gif";
  images[10]="/images/buttons/11r.gif";
  images[11]="/images/buttons/12r.gif";
  images[12]="/images/buttons/13r.gif";
  images[13]="/images/buttons/13r.gif";
  images[14]="/images/buttons/15r.gif";
  images[15]="/images/buttons/16r.gif";
  images[16]="/images/buttons/17r.gif";
  images[17]="/images/buttons/18r.gif";
  images[18]="/images/buttons/19r.gif";
  // start preloading
  for(i=0; i<=18; i++) {
	(new Image()).src=images[i];
  }
}