diff --git a/change_log.txt b/change_log.txt
index 4964fd2f..75f35152 100644
--- a/change_log.txt
+++ b/change_log.txt
@@ -1,6 +1,7 @@
 ===== trunk  =====
 12.04.2012
-- Smarty did eat the linebreak after the <?xml...?> closing tag (Issue 93)
+- bugfix Smarty did eat the linebreak after the <?xml...?> closing tag (Issue 93)
+- bugfix concurrent cache updates could create a warning (Forum Topic 21403)
 
 08.04.2012
 - bugfix "\\" was not escaped correctly when generating nocache code (Forum Topic 21364)
diff --git a/libs/sysplugins/smarty_internal_cacheresource_file.php b/libs/sysplugins/smarty_internal_cacheresource_file.php
index 25195412..e5d20bd6 100644
--- a/libs/sysplugins/smarty_internal_cacheresource_file.php
+++ b/libs/sysplugins/smarty_internal_cacheresource_file.php
@@ -100,9 +100,11 @@ class Smarty_Internal_CacheResource_File extends Smarty_CacheResource {
     public function writeCachedContent(Smarty_Internal_Template $_template, $content)
     {
         if (Smarty_Internal_Write_File::writeFile($_template->cached->filepath, $content, $_template->smarty) === true) {
-            $_template->cached->timestamp = filemtime($_template->cached->filepath);
+            $_template->cached->timestamp = @filemtime($_template->cached->filepath);
             $_template->cached->exists = !!$_template->cached->timestamp;
-            return true;
+            if ($_template->cached->exists) {
+                return true;
+            }
         }
         return false;
     }