List of locales supported by Facebook. These are the same supported locales that you can only call when loading the FB JS SDK

FB Locale List

<?php
/**
 * List of locales supported by Facebook.
 * 
 * These are the same supported locales that you can only call when loading the FB JS SDK at
 * //connect.facebook.net/{LOCALE_ID}/all.js
 * 
 * Locales taken from http://www.facebook.com/translations/FacebookLocales.xml
 * 
 * Last Updated: 04/09/2012
 * 
 * @author SVC Invoke <dev@svcapps.com>
 * @organisation Invoke <www.invokemedia.com>
 */
$config = array(
	// Afrikaans
	'af_ZA' => 'af_ZA',
	// Arabic
	'ar_AR' => 'ar_AR',
	// Azerbaijani
	'az_AZ' => 'az_AZ',
	// Belarusian
	'be_BY' => 'be_BY',
	// Bulgarian
	'bg_BG' => 'bg_BG',
	// Bengali
	'bn_IN' => 'bn_IN',
	// Bosnian
	'bs_BA' => 'bs_BA',
	// Catalan
	'ca_ES' => 'ca_ES',
	// Czech
	'cs_CZ' => 'cs_CZ',
	// Welsh
	'cy_GB' => 'cy_GB',
	// Danish
	'da_DK' => 'da_DK',
	// German
	'de_DE' => 'de_DE',
	// Greek
	'el_GR' => 'el_GR',
	// English (UK)
	'en_GB' => 'en_GB',
	// English (Pirate)
	'en_PI' => 'en_PI',
	// English (Upside Down)
	'en_UD' => 'en_UD',
	// English (US)
	'en_US' => 'en_US',
	// Esperanto
	'eo_EO' => 'eo_EO',
	// Spanish (Spain)
	'es_ES' => 'es_ES',
	// Spanish
	'es_LA' => 'es_LA',
	// Estonian
	'et_EE' => 'et_EE',
	// Basque
	'eu_ES' => 'eu_ES',
	// Persian
	'fa_IR' => 'fa_IR',
	// Leet Speak
	'fb_LT' => 'fb_LT',
	// Finnish
	'fi_FI' => 'fi_FI',
	// Faroese
	'fo_FO' => 'fo_FO',
	// French (Canada)
	'fr_CA' => 'fr_CA',
	// French (France)
	'fr_FR' => 'fr_FR',
	// Frisian
	'fy_NL' => 'fy_NL',
	// Irish
	'ga_IE' => 'ga_IE',
	// Galician
	'gl_ES' => 'gl_ES',
	// Hebrew
	'he_IL' => 'he_IL',
	// Hindi
	'hi_IN' => 'hi_IN',
	// Croatian
	'hr_HR' => 'hr_HR',
	// Hungarian
	'hu_HU' => 'hu_HU',
	// Armenian
	'hy_AM' => 'hy_AM',
	// Indonesian
	'id_ID' => 'id_ID',
	// Icelandic
	'is_IS' => 'is_IS',
	// Italian
	'it_IT' => 'it_IT',
	// Japanese
	'ja_JP' => 'ja_JP',
	// Georgian
	'ka_GE' => 'ka_GE',
	// Khmer
	'km_KH' => 'km_KH',
	// Korean
	'ko_KR' => 'ko_KR',
	// Kurdish
	'ku_TR' => 'ku_TR',
	// Latin
	'la_VA' => 'la_VA',
	// Lithuanian
	'lt_LT' => 'lt_LT',
	// Latvian
	'lv_LV' => 'lv_LV',
	// Macedonian
	'mk_MK' => 'mk_MK',
	// Malayalam
	'ml_IN' => 'ml_IN',
	// Malay
	'ms_MY' => 'ms_MY',
	// Norwegian (bokmal)
	'nb_NO' => 'nb_NO',
	// Nepali
	'ne_NP' => 'ne_NP',
	// Dutch
	'nl_NL' => 'nl_NL',
	// Norwegian (nynorsk)
	'nn_NO' => 'nn_NO',
	// Punjabi
	'pa_IN' => 'pa_IN',
	// Polish
	'pl_PL' => 'pl_PL',
	// Pashto
	'ps_AF' => 'ps_AF',
	// Portuguese (Brazil)
	'pt_BR' => 'pt_BR',
	// Portuguese (Portugal)
	'pt_PT' => 'pt_PT',
	// Romanian
	'ro_RO' => 'ro_RO',
	// Russian
	'ru_RU' => 'ru_RU',
	// Slovak
	'sk_SK' => 'sk_SK',
	// Slovenian
	'sl_SI' => 'sl_SI',
	// Albanian
	'sq_AL' => 'sq_AL',
	// Serbian
	'sr_RS' => 'sr_RS',
	// Swedish
	'sv_SE' => 'sv_SE',
	// Swahili
	'sw_KE' => 'sw_KE',
	// Tamil
	'ta_IN' => 'ta_IN',
	// Telugu
	'te_IN' => 'te_IN',
	// Thai
	'th_TH' => 'th_TH',
	// Filipino
	'tl_PH' => 'tl_PH',
	// Turkish
	'tr_TR' => 'tr_TR',
	// Ukrainian
	'uk_UA' => 'uk_UA',
	// Vietnamese
	'vi_VN' => 'vi_VN',
	// Simplified Chinese (China)
	'zh_CN' => 'zh_CN',
	// Traditional Chinese (Hong Kong)
	'zh_HK' => 'zh_HK',
	// Traditional Chinese (Taiwan)
	'zh_TW' => 'zh_TW',
);