document.writeln('<a href="http://captchas.net"><img style="border: none; vertical-align: bottom" id="captchas.net" src="http://image.captchas.net/?client=tansohkeong&random=243c8e3c5cc2230&alphabet=abcdefghkmnopqrstuvwxyz" width="180" height="50" alt="The CAPTCHA image" /></a>') 
  function captchas_image_error (image)
  {
    if (!image.timeout) return true;
    image.src = image.src.replace (/^http:\/\/image\.captchas\.net/,
                                'http://image.backup.captchas.net');
    return captchas_image_loaded (image);
  }

  function captchas_image_loaded (image)
  {
    if (!image.timeout) return true;
    window.clearTimeout (image.timeout);
    image.timeout = false;
    return true;
  }

  var image = document.getElementById ('captchas.net');
  image.onerror = function() {return captchas_image_error (image);};
  image.onload = function() {return captchas_image_loaded (image);};
  image.timeout 
    = window.setTimeout(
    "captchas_image_error (document.getElementById ('captchas.net'))",
    10000);
  image.src = image.src;