if(navigator.appVersion.charAt(0) >= 3) {
 var img = new Array();
 img[0] = new Image();  img[0].src = "images/b_product.gif";
 img[1] = new Image();  img[1].src = "images/bo_product.gif";
 img[2] = new Image();  img[2].src = "images/b_work_list.gif";
 img[3] = new Image();  img[3].src = "images/bo_work_list.gif";
 img[4] = new Image();  img[4].src = "images/b_work_touroku.gif";
 img[5] = new Image();  img[5].src = "images/bo_work_touroku.gif";
 img[6] = new Image();  img[6].src = "images/b_staff_touroku.gif";
 img[7] = new Image();  img[7].src = "images/bo_staff_touroku.gif";
 img[8] = new Image();  img[8].src = "images/b_gaiyou.gif";
 img[9] = new Image();  img[9].src = "images/bo_gaiyou.gif";
 img[10] = new Image();  img[10].src = "images/b_form.gif";
 img[11] = new Image();  img[11].src = "images/bo_form.gif";

}
function change_image(nam,num) {
  if(navigator.appVersion.charAt(0) >= 3) {
    document.images[nam].src = img[num].src;
  }
}