diff -r 5a6b6e770365 -r 68c69c656a2c web/lib/Zend/Cache/Backend/File.php
--- a/web/lib/Zend/Cache/Backend/File.php	Thu May 07 15:10:09 2015 +0200
+++ b/web/lib/Zend/Cache/Backend/File.php	Thu May 07 15:16:02 2015 +0200
@@ -15,9 +15,9 @@
  * @category   Zend
  * @package    Zend_Cache
  * @subpackage Zend_Cache_Backend
- * @copyright  Copyright (c) 2005-2012 Zend Technologies USA Inc. (http://www.zend.com)
+ * @copyright  Copyright (c) 2005-2015 Zend Technologies USA Inc. (http://www.zend.com)
  * @license    http://framework.zend.com/license/new-bsd     New BSD License
- * @version    $Id: File.php 24844 2012-05-31 19:01:36Z rob $
+ * @version    $Id$
  */
 
 /**
@@ -34,7 +34,7 @@
 /**
  * @package    Zend_Cache
  * @subpackage Zend_Cache_Backend
- * @copyright  Copyright (c) 2005-2012 Zend Technologies USA Inc. (http://www.zend.com)
+ * @copyright  Copyright (c) 2005-2015 Zend Technologies USA Inc. (http://www.zend.com)
  * @license    http://framework.zend.com/license/new-bsd     New BSD License
  */
 class Zend_Cache_Backend_File extends Zend_Cache_Backend implements Zend_Cache_Backend_ExtendedInterface
@@ -120,7 +120,6 @@
      *
      * @param  array $options associative array of options
      * @throws Zend_Cache_Exception
-     * @return void
      */
     public function __construct(array $options = array())
     {
@@ -234,10 +233,10 @@
      * Note : $data is always "string" (serialization is done by the
      * core not by the backend)
      *
-     * @param  string $data             Datas to cache
-     * @param  string $id               Cache id
-     * @param  array  $tags             Array of strings, the cache record will be tagged by each string entry
-     * @param  int    $specificLifetime If != false, set a specific lifetime for this cache record (null => infinite lifetime)
+     * @param  string      $data             Datas to cache
+     * @param  string      $id               Cache id
+     * @param  array       $tags             Array of strings, the cache record will be tagged by each string entry
+     * @param  boolean|int $specificLifetime If != false, set a specific lifetime for this cache record (null => infinite lifetime)
      * @return boolean true if no problem
      */
     public function save($data, $id, $tags = array(), $specificLifetime = false)
@@ -303,7 +302,7 @@
      *                                               ($tags can be an array of strings or a single string)
      *
      * @param string $mode clean mode
-     * @param tags array $tags array of tags
+     * @param array $tags array of tags
      * @return boolean true if no problem
      */
     public function clean($mode = Zend_Cache::CLEANING_MODE_ALL, $tags = array())
@@ -675,14 +674,17 @@
             // On some systems it is impossible to distinguish between empty match and an error.
             return true;
         }
+        $metadataFiles = array();
         foreach ($glob as $file)  {
             if (is_file($file)) {
                 $fileName = basename($file);
                 if ($this->_isMetadatasFile($fileName)) {
-                    // in CLEANING_MODE_ALL, we drop anything, even remainings old metadatas files
-                    if ($mode != Zend_Cache::CLEANING_MODE_ALL) {
-                        continue;
+                    // In CLEANING_MODE_ALL, we drop anything, even remainings old metadatas files.
+                    // To do that, we need to save the list of the metadata files first.
+                    if ($mode == Zend_Cache::CLEANING_MODE_ALL) {
+                        $metadataFiles[] = $file;
                     }
+                    continue;
                 }
                 $id = $this->_fileNameToId($fileName);
                 $metadatas = $this->_getMetadatas($id);
@@ -691,12 +693,7 @@
                 }
                 switch ($mode) {
                     case Zend_Cache::CLEANING_MODE_ALL:
-                        $res = $this->remove($id);
-                        if (!$res) {
-                            // in this case only, we accept a problem with the metadatas file drop
-                            $res = $this->_remove($file);
-                        }
-                        $result = $result && $res;
+                        $result = $result && $this->remove($id);
                         break;
                     case Zend_Cache::CLEANING_MODE_OLD:
                         if (time() > $metadatas['expire']) {
@@ -753,6 +750,14 @@
                 }
             }
         }
+
+        // cycle through metadataFiles and delete orphaned ones
+        foreach ($metadataFiles as $file) {
+            if (file_exists($file)) {
+                $result = $this->_remove($file) && $result;
+            }
+        }
+
         return $result;
     }
 
@@ -843,6 +848,7 @@
     /**
      * Compute & return the expire time
      *
+     * @param  int $lifetime
      * @return int expire time (unix timestamp)
      */
     protected function _expireTime($lifetime)