title: jQuery scrollstart, scrollstop and very quick scrolling issue
body: <p>I'm having an issue with <a href="http://james.padolsey.com/javascript/special-scroll-events-for-jquery/" rel="nofollow">James Padolsey's custom events</a>: <code>scrollstart</code> and <code>scrolltop</code></p>
  
  <p>When I use the mouse wheel to scroll one "notch" or I click the scroll bar somewhere far below or above its current position, causing sudden scroll by a large amount, I get the same <code>scrollTop()</code> values for <code>scrollstart</code> and <code>scrolltop</code> - I can't tell where the scroll started or in which direction the scroll has taken place. jsFiddle available <a href="http://jsfiddle.net/mLxE4/3/" rel="nofollow">here</a> (note: if you have an extremely high resolution, you will have to add more text to the HTML so that a scroll bar appears in the Result window).</p>
  
  <p>HTML:</p>
  
  <pre><code>&lt;html&gt;
      &lt;body&gt;
          &lt;div id="scrollable"&gt;
              &lt;!-- insert lots of text here --&gt;
          &lt;/div&gt;
      &lt;/body&gt;
  &lt;/html&gt;
  </code></pre>
  
  <p>CSS:</p>
  
  <pre><code>#scrollable {width: 120px;}
  </code></pre>
  
  <p>JavaScript:</p>
  
  <pre><code>var before = 0;
  
  $(window).bind('scrollstart', function() {
      before = $(window).scrollTop();
  });
  
  $(window).bind('scrollstop', function() {
      alert('before: ' + before + "\nafter: " + $(window).scrollTop())
  });
  </code></pre>
  
  <p><a href="http://jsfiddle.net/mLxE4/3/" rel="nofollow">jsFiddle available here</a></p>
  
  <p>Any ideas on how to retrieve the true <code>scrollTop()</code> value for the <code>scrollstart</code> event? Modifying the plugin is an option I guess, so all ideas welcome.</p>