title: Fire event when div is visible to visitor with jQuery?
body: <p><strong>The function:</strong>
  I want to change the class of a certain item when a user see a certain div (scrolls down to it).</p>
  
  <p><strong>How I do it now:</strong> I'm using this fine script (<a href="http://code.google.com/p/jquery-appear/" rel="nofollow">http://code.google.com/p/jquery-appear/</a>) wich works really fine to just fire an jquery event when a div gets visible to the user. However it only fires once. So if you scroll down the page the jquery gets executed fine. But if I scroll up and then down again it doesent fire. This is my jquery:</p>
  
  <pre><code>$('#myDiv').appear(function() {
          $("#aDiv").addClass("active");
  });
  </code></pre>
  
  <p><strong>What I want to do:</strong> Make the script execute everytime "myDiv" appear and not only the first.</p>
  
  <p>Does anyone have an idea on how I could do this?</p>