$("input[id^='Date-<%=Model.ID%>']").datepicker({
            duration: 0,
            buttonImage: '/Content/images/calender.gif',
            buttonImageOnly: true, 
            showOn:'button',
            constrainInput: true,
            showTime: true,
            stepMinutes: 30,
            stepHours: 1,
            altTimeField: '',
            time24h: true,
            minDate: 0
        });

I have this Calender Control I am using..user can select any date from the calender.. I need to validate the dates like Saturday and Sundays and 1/1 and 1/25.. if they select these days I need to show them Popup message not valid date?

can anybody help me out.. thanks