var Ajax;
if (Ajax && (Ajax != null)) {
  Ajax.Responders.register({
    onCreate: function() {
        if($('spinner') && Ajax.activeRequestCount>0)
          Effect.Appear('spinner',{duration:0.5,queue:'end'});
    },
    onComplete: function() {
        if($('spinner') && Ajax.activeRequestCount==0)
          Effect.Fade('spinner',{duration:0.5,queue:'end'});
    }
  });
}