i18n: Default culture not loaded by default

The problem is here (/lib/symfony.php):

96: if (sfConfig::get('sf_i18n'))
97: {
98:   include($configCache->checkConfig($sf_app_config_dir_name.'/i18n.yml'));
99: }

I sugguest to remove the If statement.

The idea is to separate those two things:

1) the default culture for non-i18n application,
2) settings for i18n application (those are set in i18n.yml file).

So, better suggestion would be to move the "default_culture" from the i18n.yml to settings.yml. Therefore leaving i18n settings in i18n.yml and the default_culture in settings.yml.

in r6721