diff --git wp-includes/l10n.php wp-includes/l10n.php
index 733f3a4..91d211f 100644
--- wp-includes/l10n.php
+++ wp-includes/l10n.php
@@ -434,22 +434,28 @@ function load_muplugin_textdomain( $domain, $mu_plugin_rel_path = '' ) {
 /**
  * Loads the theme's translated strings.
  *
- * If the current locale exists as a .mo file in the theme's root directory, it
- * will be included in the translated strings by the $domain.
+ * If a .mo file is found, it will be included in the translated strings
+ * by the $domain.
  *
  * The .mo files must be named based on the locale exactly.
  *
  * @since 1.5.0
  *
  * @param string $domain Unique identifier for retrieving translated strings
+ * @param string $path The path to the .mo file directory (optional)
  */
 function load_theme_textdomain( $domain, $path = false ) {
 	$locale = apply_filters( 'theme_locale', get_locale(), $domain );
 
-	$path = ( empty( $path ) ) ? get_template_directory() : $path;
+	$mofile = WP_LANG_DIR . "/themes/$domain-$locale.mo";
 
-	$mofile = "$path/$locale.mo";
-	return load_textdomain($domain, $mofile);
+	if ( !is_readable( $mofile ) ) {
+		if ( empty( $path ) )
+			$path = get_template_directory();
+		$mofile = "$path/$locale.mo";
+	}
+
+	return load_textdomain( $domain, $mofile );
 }
 
 /**