UserControl with DateTime property

Hi everyone,
I created a UserControl and added a public DateTime property. I want to set this property in Markup (ie. <cc1:MyControl runat="server" id="MyControl1" DateTimeProp="1/1/2010" /> ) however I live in a place with a dd/mm/yyyy date format so it complains if I set something like "20/1/2010". Is there a way to set markup in my local datetime format or do I have to conform to "mm/dd/yyyy"?
Regards,
Mark.
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