--- a/includes/file.inc	Tue Dec 23 14:32:19 2008 +0100
+++ b/includes/file.inc	Tue Dec 23 14:32:33 2008 +0100
@@ -1,5 +1,5 @@
 <?php
-// $Id: file.inc,v 1.121.2.4 2008/09/17 08:13:07 goba Exp $
+// $Id: file.inc,v 1.121.2.5 2008/10/20 09:42:31 goba Exp $
 
 /**
  * @file
@@ -792,7 +792,9 @@
  * @param $headers An array of http headers to send along with file.
  */
 function file_transfer($source, $headers) {
-  ob_end_clean();
+  if (ob_get_level()) {
+    ob_end_clean();
+  }
 
   foreach ($headers as $header) {
     // To prevent HTTP header injection, we delete new lines that are