Extensible.calendar.CalendarPanel

Hello,

I am trying to create a Extensible calendar panel. 

 _{<link href="../../Scripts/Ext/resources/css/ext-all.css" rel="stylesheet" type="text/css" />}

    _{<script src="../../Scripts/Ext/ext-all-debug.js" type="text/javascript"></script>}

    _{<!--Calendar -->}

    _{<link href="../../Scripts/Calendar/extensible-all.css" rel="stylesheet" type="text/css" />}

    _{<script src="../../Scripts/Calendar/src/Extensible.js" type="text/javascript"></script>}

    _{<script src="../../Scripts/Calendar/extensible-all.js" type="text/javascript"></script>}

The above code is my html header. However Extensible.calendar.EventRecord.reconfigure(); is always undefined. Do I miss thing in the header?