if (document.images) {
 var img = new Array();

 img[60] = new Image();  img[60].src = "../img/button_details.gif";
 img[61] = new Image();  img[61].src = "../img/button_details_on.gif";

 img[62] = new Image();  img[62].src = "../img/button_buy.gif";
 img[63] = new Image();  img[63].src = "../img/button_buy_on.gif";

 img[64] = new Image();  img[64].src = "../img/button_back.gif";
 img[65] = new Image();  img[65].src = "../img/button_back_on.gif";

}

function swapImg(name,num) {
 if (document.images) {
    document.images[name].src = img[num].src;
 }
}