title: jQuery AJAX Post doesn't work
body: <p>I can't figure out why the following code doesn't work.  For the time being, the php function "alias_valid"  just returns a string for testing purposes, so I haven't included the php function here. The alert is empty.</p>
  
  <pre><code>$.post(SITE_ROOT + "includes/AbstractEvent.php",{
      action:"alias_valid", 
      alias : alias},
      function(v){
          alert(v);
      });
  </code></pre>