diff --git a/activesupport/lib/active_support/callbacks.rb b/activesupport/lib/active_support/callbacks.rb
index ba9fb4eccea4f..2ebafa28dda69 100644
--- a/activesupport/lib/active_support/callbacks.rb
+++ b/activesupport/lib/active_support/callbacks.rb
@@ -381,9 +381,8 @@ def __define_runner(symbol) #:nodoc:
         name = __callback_runner_name(nil, symbol)
         undef_method(name) if method_defined?(name)
 
-        silence_warnings do
-          runner_method = "_run_#{symbol}_callbacks" 
-          undef_method runner_method if method_defined?(runner_method)
+        runner_method = "_run_#{symbol}_callbacks" 
+        unless private_method_defined?(runner_method)
           class_eval <<-RUBY_EVAL, __FILE__, __LINE__ + 1
             def #{runner_method}(key = nil, &blk)
               self.class.__run_callback(key, :#{symbol}, self, &blk)