I am preparing the upgrade of one RoR aplication that used Rails 2.3.8 and where all the translations worked fine. Now I discovered that it is not the case any more. Everything seems to work fien except the Error windows header where the interpolation is not recognized. I'm using Rails 3.0.3, Ruby 1.9.2. I've just created a simple application, downloaded the latest french YML file from I18n github and added a simple validation: [code] class Client < ActiveRecord::Base validates :firstname, :lastname, :presence=> true end [/code] Then I modified the 'application.rb' file as follows: [code] config.i18n.load_path += Dir[Rails.root.join('my', 'locales', '*. {rb,yml}').to_s] config.i18n.default_locale = :fr [/code] Then I tried to save a Client by leaving the mandatory fields empty and got: [code] "Impossible d'enregistrer ce %{model} : %{count} erreurs" [/code] as the header of the Errors dialog window. As you see, the interpolation was taken as it is instead of putting the Model name and errors number. The rest of validation message was translated correctly. Any idea?