When you set up your DatePicker inputs on the page, try this:
$('.DatePicker').datepicker({
dayNamesMin: ['<%= string.Join("', '", System.Globalization.DateTimeFormatInfo.CurrentInfo.ShortestDayNames) %>'],
monthNames: ['<%= string.Join("', '", System.Globalization.DateTimeFormatInfo.CurrentInfo.MonthNames) %>'],
monthNamesShort: ['<%= string.Join("', '", System.Globalization.DateTimeFormatInfo.CurrentInfo.AbbreviatedMonthNames) %>']
});