(function($){
   $.fn.linkedSelect = function(url,destination,params) {
      var params = $.extend({
         firstOption : 'Please Select',
         loadingText : 'Loading...'
      },params);
      var $dest = $(destination);
      return this.each(function(){
         $(this).bind('change', function() {
            var $$ = $(this);
            $dest.attr('disabled','false')
                 .append('<option value="">' +params.loadingText+ '</option>')
                 .ajaxStart(function(){
                    $$.show();
            });
            $.getJSON(url,{str: $$.val() }, function(j){
               if (j.length > 0) {
                  var options = '<option value="">' +params.firstOption+ '</option>';
                  for (var i = 0; i < j.length; i++) {
                     options += '<option value="' + j[i].optionValue + '">' + j[i].optionDisplay + '</option>';
                  }
               }
               $dest.removeAttr('disabled')
                    .html(options)
                    .find('option:first')
                    .attr('selected', 'selected');
            }); // end getJSON
         });  // end change
      }); // end return each
  };  // end function
})(jQuery);