title: Jquery droppable live disabling/enabling
body: <p>I have a some draggables in a list of droppables (1 draggable per droppable li).  </p>
  
  <p>When I move a draggable from one droppable to another free droppable, I want to diable the receiving droppable, and enable the droppable it is leaving from. </p>
  
  <p>In firebug the droppable class gets removed – but the functionality of the droppable remains.  I have a feeling I need to use live() somehow, but could use a leg-up.</p>
  
  <pre><code>$(function() {
  $(".user").draggable({
    revert          : true, 
    revertDuration  : 200
  });
  
  
    $("li.droppable").droppable({
      accept      : ".user",
      hoverClass  : "drophover",
      drop: function(event, ui) {
        var position  = this.getAttribute("id").replace("position_", ""),
          user_id = ui.draggable.attr("id").replace("user_", "");
          droppable = this
          parent    = ui.draggable.parent()
        $.ajax({
          url   : "users/"+user_id+"",
          type  : "POST",
          dataType: "JSON",
          data  : ({
            "position"  : position,
            "_method"   : "PUT"
          }),
          success : function() {
            $(ui.draggable).parent().addClass("droppable");
            $(ui.draggable).appendTo(droppable);
            $(parent).removeClass("droppable");
          }
        });
      }
    });
  });
  </code></pre>