Java locale has 3 components: language, country & variant. The JSF 1.2 schema (web-facesconfig_1_2.xsd) documentation correctly states the handling of these:
The "supported-locale" element allows authors to declare which locales are supported
in this application instance. It must be specified as :language:[_:country:[_:variant:]]
without the colons, for example "ja_JP_SJIS". The separators between the segments may be '-' or '_'.
However, the schema pattern definition for faces-config-localeType is:
which only supports the language_COUNTRY format.
The correct pattern should be:
Update the faces-config-localeType regular expression accordingly.
The documentation describes the correct locale pattern. The pattern in the schema document is incorrect.