function AddFav(url,alt,txt) {
        if (navigator.userAgent.indexOf('MSIE')>0 ) {
                ver = parseInt(navigator.appVersion);
                if (ver > 3) window.external.AddFavorite(url,alt);
                if (ver > 4) this.SetHomePage(url);
        }
}

function img_b(ni)
{
  if(current != ('td_num'+ni))
  {
    ob = document.getElementById('rt_img');
    ob.src = img_a[ni].src;
    ob.alt = img_alt[ni];
    document.getElementById("rt_url").href = img_link[ni];
    var st = 'td_num'+ni;
    ob_td = document.getElementById(st);
    ob_td.className = 'rt_brd_active';
    curob = document.getElementById(current);
    curob.className = 'rt_brd_passive';
    current = st;
  }
}