This plugin adds the ability to add an ISO 639-3 language code to the custom field of a post.
ISO 639-3 codes are codes for the representation of names of languages. ISO 639-3 attempts to provide as complete an enumeration of languages as possible, including living, extinct, ancient, and constructed languages, whether major or minor, written or unwritten. More information can be found at http://www.sil.org/iso639-3/.
The ISO does but, you can contact the registrar, SIL International.
Everything you need to make this plugin work with wordpress ships with the plugin. However in our code we have used the ISO 639-3 UTF-8 table provided by SIL International http://www.sil.org/ISO639-3/iso-639-3_20090210.tab This table is updated annualy. We also have used and modified the jQuery autocomplete script made availible by PengoWorks.Com (http://www.pengoworks.com/workshop/jquery/autocomplete.htm "http://www.pengoworks.com/workshop/jquery/autocomplete.htm")