Normal1 = new Image();
Normal1.src = "images/header_account_sw.png";     /* erste Standard-Grafik */
Highlight1 = new Image();
Highlight1.src = "images/header_account.png"; /* erste Highlight-Grafik */

Normal2 = new Image();
Normal2.src = "images/header_cart_sw.png";     /* erste Standard-Grafik */
Highlight2 = new Image();
Highlight2.src = "images/header_cart.png"; /* erste Highlight-Grafik */

Normal3 = new Image();
Normal3.src = "images/header_checkout_sw.png";     /* erste Standard-Grafik */
Highlight3 = new Image();
Highlight3.src = "images/header_checkout.png"; /* erste Highlight-Grafik */

Normal4  = new Image();
Normal4.src  = "button_continue_sw.gif";     /* erste Standard-Grafik */
Highlight4 = new Image();
Highlight4.src = "button_continue.gif"; /* erste Highlight-Grafik */

function Bildwechsel (Bildnr, Bildobjekt) {
  window.document.images[Bildnr].src = Bildobjekt.src;
}