Request.implement({queue:function(a){if(!$defined(this.queued)){this.queued=[];}this.queued.push(a);this.processQueue();},processQueue:function(){if(this.timer){$clear(this.timer);}if(!this.check()){this.timer=this.processQueue.delay(250,this);}else{if($defined(this.queued[0])){this.send(this.queued.shift());this.processQueue();}else{this.fireEvent("onQueueEmpty");}}}});