Found here
Code:
en_AU Australia
en_BW Botswana
en_CA Canada
en_GB Great Britain (should be UK, hmph!)
en_HK Hong Kong
en_IE Ireland
en_IN India
en_MT Malta
en_NZ New zealand
en_PH Phillipines
en_SG Singapore
en_US United States
en_US_POSIX U.S. POSIX
en_VI Virgin Islands
en_ZA South Africa
en_ZW Zimbabwe