diff --git a/actionpack/lib/action_view/template/handlers.rb b/actionpack/lib/action_view/template/handlers.rb
index 0590372d09..faf54b9fe5 100644
--- a/actionpack/lib/action_view/template/handlers.rb
+++ b/actionpack/lib/action_view/template/handlers.rb
@@ -33,7 +33,7 @@ module ActionView #:nodoc:
     end
 
     def template_handler_extensions
-      @@template_handlers.keys.map(&:to_s).sort
+      @@template_handlers.keys.map {|key| key.to_s }.sort
     end
 
     def registered_template_handler(extension)