title: Javascript: onScroll event (using Prototype) doesn't work on IE?
body: <p>I am trying to trigger the onScroll event this way using prototype:</p>
  
  <pre><code>Event.observe(document, 'scroll', function(){
      alert('boo');
  });
  </code></pre>
  
  <p>It works perfectly on Firefox, but nothing happens on IE. Does anyone know why? and if there is another way to do so?</p>
  
  <p>Thanks</p>