Index: wp-includes/l10n.php
===================================================================
--- wp-includes/l10n.php	(revision 11136)
+++ wp-includes/l10n.php	(working copy)
@@ -336,6 +336,8 @@
  */
 function load_plugin_textdomain($domain, $abs_rel_path = false, $plugin_rel_path = false) {
 	$locale = get_locale();
+	
+	$locale = apply_filters('plugin_locale', $locale, $domain);
 
 	if ( false !== $plugin_rel_path	)
 		$path = WP_PLUGIN_DIR . '/' . trim( $plugin_rel_path, '/');
@@ -362,6 +364,8 @@
  */
 function load_theme_textdomain($domain, $path = false) {
 	$locale = get_locale();
+	
+	$locale = apply_filters('theme_locale', $locale, $domain);
 
 	$path = ( empty( $path ) ) ? get_template_directory() : $path;