You can see an example how to bind datepicker to database here: http://demos.telerik.com/aspnet-ajax/calendar/examples/datepicker/databinding/defaultcs.aspx
Actually it uses pretty much the same workaround. But currently we are not planning to change this behavior. It is a general issue with binding nullable types from the database. The DatePicker itself uses DateTime type which is standard type in .Net. And this ensures that all users could easily manipulate with it and bind it to various datasources, even if sometimes they will need to cast it first.
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