1 files changed, 3 insertions, 4 deletions
diff --git a/activemodel/lib/active_model/observing.rb b/activemodel/lib/active_model/observing.rb
index d48f2e8a1f..cd8eb357de 100644
--- a/activemodel/lib/active_model/observing.rb
+++ b/activemodel/lib/active_model/observing.rb
@@ -187,8 +187,7 @@ module ActiveModel
       def observe(*models)
         models.flatten!
         models.collect! { |model| model.respond_to?(:to_sym) ? model.to_s.camelize.constantize : model }
-        remove_possible_method(:observed_classes)
-        define_method(:observed_classes) { models }
+        redefine_method(:observed_classes) { models }
       end
 
       # Returns an array of Classes to observe.
@@ -226,10 +225,10 @@ module ActiveModel
 
     # Send observed_method(object) if the method exists and
     # the observer is enabled for the given object's class.
-    def update(observed_method, object) #:nodoc:
+    def update(observed_method, object, &block) #:nodoc:
       return unless respond_to?(observed_method)
       return if disabled_for?(object)
-      send(observed_method, object)
+      send(observed_method, object, &block)
     end
 
     # Special method sent by the observed class when it is inherited.