Index: locale.module
===================================================================
--- locale.module	(revision 25)
+++ locale.module	(working copy)
@@ -551,7 +551,10 @@
 
   // Add the translation JavaScript file to the page.
   if ($files && !empty($language->javascript)) {
-    drupal_add_js($dir .'/'. $language->language .'_'. $language->javascript .'.js', 'core');
+    $path = $dir .'/'. $language->language .'_'. $language->javascript .'.js';
+    if (file_exists($path)) {
+      drupal_add_js($path, 'core', 'header', FALSE, FALSE);
+    }
   }
 }