The localized version of the JavaStation software supports all the locales described in "Setting the Locale". At login, the user is asked to choose one of these locales.
If you want to restrict or add to the locales presented at login, especially if you will be running an application that is localized for a language not listed in "Setting the Locale", you must modify the javaos.loginLocaleList property.
where each locale is defined using one of the two-letter codes that define user.language followed by (in some cases) an underscore character and one of the two-letter codes that define user.country.
The default value of this property is:
-djavaos.loginLocaleList=en_US
Thus by default U.S. English is the only language choice available at login.