How to disable telerik validation?

Question

I m using Telerik raddatepicker. My Telerik version is 2009.

While setting fields, I'm getting range validation alert. but the field is what I enter. Screenshot

   set_rangeMinDate: function(_8b) {
       if (this.RangeValidation.CompareDates(_8b, this.RangeMaxDate) > 0) {
            alert("RangeMinDate should be less than the RangeMaxDate value!");
            return;
       }
       ...
       ...
       ...
   }