Custom Datetime Picker

[wjburke2]

I have a form with several DateTime fields many will remain blank and are nullable fields on the database. Of course the problem is the datetime picker will not allow null values. My solution is to make the field a textbox and format the data in the advanced option of the binding. This works but now I would like to add a button that will popup a datetime picker and allow the user to select the date from a calendar. I know I have seen such a thing in the past but can't seem to find the code now. Can anyone help.