So if my start date is : 04/22/2010 then my end date selection can be up to 04/22/2011 and after 04/22/2011 are dates all disabled.

Here is what I have for both selection start and end date:

$(document).ready(function () {      
  $('#endDate').datepicker({ showOn: 'button', 
      buttonImage: '../images/Calendar.png', 
      buttonImageOnly: true, onSelect: function () { }, 
      onClose: function () { $(this).focus(); } 
    }); 

  $('#startDate').datepicker({ showOn: 'button', 
      buttonImage: '../images/Calendar.png', 
      buttonImageOnly: true, onSelect: 
        function (dateText, inst) { 
          $('#endDate').datepicker("option", 'minDate', new Date(dateText)); 
        } 
      , 
      onClose: function () { $(this).focus(); } 
    }); 
});