diff --git a/activesupport/lib/active_support/duration.rb b/activesupport/lib/active_support/duration.rb
index a535e2b668..de3ded1e1f 100644
--- a/activesupport/lib/active_support/duration.rb
+++ b/activesupport/lib/active_support/duration.rb
@@ -99,7 +99,7 @@ def sum(sign, time = ::Time.current) #:nodoc:
     private
 
       def method_missing(method, *args, &block) #:nodoc:
-        value.send(method, *args)
+        value.send(method, *args, &block)
       end
   end
 end
diff --git a/activesupport/test/core_ext/duration_test.rb b/activesupport/test/core_ext/duration_test.rb
index 8469f78566..b6456f0a30 100644
--- a/activesupport/test/core_ext/duration_test.rb
+++ b/activesupport/test/core_ext/duration_test.rb
@@ -129,6 +129,14 @@ def test_adding_day_across_dst_boundary
       assert_equal Time.local(2009,3,29,0,0,0) + 1.day, Time.local(2009,3,30,0,0,0)
     end
   end
+  
+  def test_delegation_with_block_works
+    counter = 0
+    assert_nothing_raised do
+      1.minute.times {counter += 1}
+    end
+    assert_equal counter, 60
+  end
 
   protected
     def with_env_tz(new_tz = 'US/Eastern')