diff --git a/config/initializers/10-patches.rb b/config/initializers/10-patches.rb
index fcc091997..5fbb91abf 100644
--- a/config/initializers/10-patches.rb
+++ b/config/initializers/10-patches.rb
@@ -12,6 +12,6 @@ ActiveRecord::Errors.default_error_messages = {
   :wrong_length => "activerecord_error_wrong_length",
   :taken => "activerecord_error_taken",
   :not_a_number => "activerecord_error_not_a_number"
-}
+} if ActiveRecord::Errors.respond_to?('default_error_messages=')
 
 ActionView::Base.field_error_proc = Proc.new{ |html_tag, instance| "#{html_tag}" }