var numberOfCalendarControls = 0;

    var numberToGenerate = 1;

    var controlsHandled = [100];

    function OnEndRequest(sender,args)
            {                            
                 for(var item = 0; item < controlsHandled.length; item++)
                 {
                    controlsHandled[item] = null;
                    numberOfCalendarControls = 0;
                 }
            }
    
    function GenerateCloseButton(sender, e)

    {                   

         var prm = Sys.WebForms.PageRequestManager.getInstance();
            prm.add_endRequest(OnEndRequest);
                                            
            

        //if ($('#ajax__calendar_close_button').length == 0)

       {

        {

            var found = false;

            var lastFoundIndex = 0;
            
            for(var item = 0; item < controlsHandled.length; item++)
            {

                    if(controlsHandled[item] == sender)
                    {
                        found = true;
                    }
                    
                    if(controlsHandled[item] != null)
                    {
                        lastFoundIndex = item;
                    }

            }
            
            if(!found)
            {
            
                controlsHandled[lastFoundIndex + 1] = sender;
            
                $(sender._header).before("<div class='ajax__calendar_close_button' id='ajax__calendar_close_button" + numberOfCalendarControls + "'>x</div>");                   

                $('#ajax__calendar_close_button' + numberOfCalendarControls.toString()).bind("click", sender, function(e) {

                    e.data.hide();
                
                });
            
                numberOfCalendarControls ++;

            }

        }
    }
    }