Is en_UK an illegal locale?

Question

So far I had always used \'en_UK\' for British English. Today I got an error when using it with Zend Framework because the locale is not included in the long list of recognized

Answer 1

The correct country code is en_GB. Locales use ISO 3166-1 for country codes. The wikipedia writeup includes:

The codes are chosen, according to the ISO 3166/MA, "to reflect the significant, unique component of the country name in order to allow a visual association between country name and country code".[7] For this reason, common components of country names like "Republic", "Kingdom", "United", "Federal" or "Democratic" are normally not used for deriving the code elements. As a consequence, for example, the United Kingdom is officially assigned the alpha-2 code GB rather than UK, based on its official name "United Kingdom of Great Britain and Northern Ireland" (although UK is reserved on the request of the United Kingdom).