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After you selected your localization elements, you should determine the language ID for your language and the region ID for your region (in case you want to provide the dial plan template). Language IDs are defined based on the RFC 4646. Use just the language tag for your language or the language tag followed by the region tag if you use a language that is specific for your region (for example Mexican Spanish).
Note: When you select a language ID that uses both the language tag and the region tag, you have to make sure you use the correct separator and capitalization. Unfortunately, the language and region tags separator and the capitalization of the region tag has not been implemented in a consistent manner in the sipXecs release 3.10. The language ID is used with a dash 
( - ) as the separator and the region is used in lower case for voice prompt directory names, jar file names, and region directory names. The language ID suffix added to the names of properties files used for localization of the administrator and user portal GUI consist of a lower case language tag and an upper case region tag separated by an underscore. Due to that, for example for Mexican Spanish, you have to use the language ID "es-mx" for the voice prompt directory (stdprompts_es-mx), the jar file name (sipxconfig_es-mx.jar) and the region tag mx for the region directory (region_mx), but you have to use the suffix "es_MX" for GUI properties files (e.g., server_es_MX.properties). Changes to make these tags and separators consistent (using the underscope as the separator and the region tag in a language ID capitalized) will be considered for the next sipXecs release.
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