sharepoint date picker inside an update panel

Hello,

I hope somebody can help me on this...I placed the Sharepoint date picker control inside an update panel and when i click on the calendar it gives me this error Microsoft JScript runtime error: The value of the property 'clickDatePicker' is null or undefined, not a Function object..the control works outside the update panel without any issues...can someone please tell me how to make it work inside the panel.

Thanks