Default Language
A localeKey configuration parameter is available in the config.xml file that allows you to specify the default language used by the application. If your application has been localized, either via a language pack, or manually as described in this document, you may want to set the default language to the localized language.
The LocaleKey parameter can be set to a language code (for example, “es” for Spanish) or to a country-specific code (for example, “es_MX” for Spanish Mexico).
If the LocaleKey parameter is not set, the default language is set to that of the browser. If the LocaleKey parameter is set to a language code or country-specific code that does not match an installed language pack, or a manually localized locale, the default language defaults to “en_US” (English United States).
For more information about the localeKey parameter, see Options.