Having used Sven Fuchs' routing_filter to localize routes (see here for alternative solutions), I now moved my authentication to devise from authlogic. This broke my localized routes with the default configuration, so for example
http://localhost:3000/**en**/users/sign_in
failed with an
ActionController::UnknownAction
error.
Fixing it was super-easy, simply open your config/initializers/devise.rb file and uncomment (currently line 81)
config.use_default_scope = true
and it should work like before.
Note that this works only with Rails 2.+, not with Rails 3 where it's probably better to use a scope block to prepend locales to you routes, instead of the routing_filter plugin.