if(navigator.appVersion.charAt(0) >= "3"){
  img = new Array();
  img[0] = new Image; img[0].src = "images/index/do01.gif";
  img[1] = new Image; img[1].src = "images/index/do02.gif";
}



function chg_index(a){
  if(navigator.appVersion.charAt(0) >= "1"){
    document.images["index"].src=img[a].src;
  }
}