diff --git a/knockout.activity.js b/knockout.activity.js
index 8d9c572..3d348f8 100644
--- a/knockout.activity.js
+++ b/knockout.activity.js
@@ -233,7 +233,7 @@
 })(jQuery);
 
 
-// By: Hans Fjällemark and John Papa
+// By: Hans Fj�llemark and John Papa
 // https://github.com/CodeSeven/KoLite
 
 ;(function($) {
@@ -374,8 +374,9 @@
         },
 
         update: function (element, valueAccessor) {
-            var activity = valueAccessor()();
+            var value = ko.utils.unwrapObservable(valueAccessor());
+            var activity = $.isFunction(value) ? value() : value;
             typeof activity !== 'boolean' || $(element).activityEx(activity);
         }
     };
-})(jQuery, ko);
\ No newline at end of file
+})(jQuery, ko);