diff --git a/lib/file_api_core.php b/lib/file_api_core.php
index 0980f96..5f60988 100644
--- a/lib/file_api_core.php
+++ b/lib/file_api_core.php
@@ -1,356 +1,360 @@
 <?php
 /*
  +--------------------------------------------------------------------------+
  | This file is part of the Kolab File API                                  |
  |                                                                          |
  | Copyright (C) 2012-2014, Kolab Systems AG                                |
  |                                                                          |
  | This program is free software: you can redistribute it and/or modify     |
  | it under the terms of the GNU Affero General Public License as published |
  | by the Free Software Foundation, either version 3 of the License, or     |
  | (at your option) any later version.                                      |
  |                                                                          |
  | This program is distributed in the hope that it will be useful,          |
  | but WITHOUT ANY WARRANTY; without even the implied warranty of           |
  | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the             |
  | GNU Affero General Public License for more details.                      |
  |                                                                          |
  | You should have received a copy of the GNU Affero General Public License |
  | along with this program. If not, see <http://www.gnu.org/licenses/>      |
  +--------------------------------------------------------------------------+
  | Author: Aleksander Machniak <machniak@kolabsys.com>                      |
  +--------------------------------------------------------------------------+
 */
 
 class file_api_core extends file_locale
 {
     const API_VERSION = 2;
 
     const ERROR_CODE    = 500;
     const ERROR_INVALID = 501;
 
     const OUTPUT_JSON = 'application/json';
     const OUTPUT_HTML = 'text/html';
 
     public $env = array(
         'date_format' => 'Y-m-d H:i',
         'language'    => 'en_US',
     );
 
     protected $app_name = 'Kolab File API';
     protected $drivers  = array();
     protected $icache   = array();
     protected $backend;
 
     /**
      * Returns API version
      */
     public function client_version()
     {
         return self::API_VERSION;
     }
 
     /**
      * Initialise authentication/configuration backend class
      *
      * @return file_storage Main storage driver
      */
     public function get_backend()
     {
         if ($this->backend) {
             return $this->backend;
         }
 
         $rcube  = rcube::get_instance();
         $driver = $rcube->config->get('fileapi_backend', 'kolab');
 
         $this->backend = $this->load_driver_object($driver);
 
         // configure api
         $this->backend->configure($this->env);
 
         return $this->backend;
     }
 
     /**
      * Return supported/enabled external storage instances
      *
      * @param bool $as_objects Return drivers as objects not config data
      *
      * @return array List of storage drivers
      */
     public function get_drivers($as_objects = false)
     {
         $rcube   = rcube::get_instance();
         $enabled = $rcube->config->get('fileapi_drivers');
         $preconf = $rcube->config->get('fileapi_sources');
         $result  = array();
         $all     = array();
         $iRony   = defined('KOLAB_DAV_ROOT');
 
         if (!empty($enabled)) {
             $backend = $this->get_backend();
             $drivers = $backend->driver_list();
 
             foreach ($drivers as $item) {
-                // Disable webdav sources/drivers in iRony
-                // It does not work when the API is used where
-                // some SabreDAV classes are redefined
+                // Disable webdav sources/drivers in iRony that point to the
+                // same host to prevent infinite recursion
                 if ($iRony && $item['driver'] == 'webdav') {
-                    continue;
+                    $self_url = parse_url($_SERVER['SCRIPT_URI']);
+                    $item_url = parse_url($item['host']);
+
+                    if ($self_url['host'] == $item_url['host']) {
+                        continue;
+                    }
                 }
 
                 $all[] = $item['title'];
 
                 if ($item['enabled'] && in_array($item['driver'], (array) $enabled)) {
                     $result[] = $as_objects ? $this->get_driver_object($item) : $item;
                 }
             }
         }
 
         if (empty($result) && !empty($preconf)) {
             foreach ((array) $preconf as $title => $item) {
                 if (!in_array($title, $all)) {
                     $item['title'] = $title;
                     $item['admin'] = true;
 
                     $result[] = $as_objects ? $this->get_driver_object($item) : $item;
                 }
             }
         }
 
         return $result;
     }
 
     /**
      * Return driver for specified file/folder path
      *
      * @param string $path Folder/file path
      *
      * @return array Storage driver object, modified path, driver config
      */
     public function get_driver($path)
     {
         $drivers = $this->get_drivers();
 
         foreach ($drivers as $item) {
             $prefix = $item['title'] . file_storage::SEPARATOR;
 
             if ($path == $item['title'] || strpos($path, $prefix) === 0) {
                 $selected = $item;
                 break;
             }
         }
 
         if (empty($selected)) {
             return array($this->get_backend(), $path);
         }
 
         $path = substr($path, strlen($selected['title']) + 1);
 
         return array($this->get_driver_object($selected), $path, $selected);
     }
 
     /**
      * Initialize driver instance
      *
      * @param array $config Driver config
      *
      * @return file_storage Storage driver instance
      */
     public function get_driver_object($config)
     {
         $key = $config['title'];
 
         if (empty($this->drivers[$key])) {
             $this->drivers[$key] = $driver = $this->load_driver_object($config['driver']);
 
             if ($config['username'] == '%u') {
                 $backend            = $this->get_backend();
                 $auth_info          = $backend->auth_info();
                 $config['username'] = $auth_info['username'];
                 $config['password'] = $auth_info['password'];
             }
             else if (!empty($config['password']) && empty($config['admin']) && !empty($key)) {
                 $config['password'] = $this->decrypt($config['password']);
             }
 
             // configure api
             $driver->configure(array_merge($config, $this->env), $key);
         }
 
         return $this->drivers[$key];
     }
 
     /**
      * Loads a driver
      */
     public function load_driver_object($name)
     {
         $class = $name . '_file_storage';
 
         if (!class_exists($class, false)) {
             $include_path = __DIR__ . "/drivers/$name" . PATH_SEPARATOR;
             $include_path .= ini_get('include_path');
             set_include_path($include_path);
         }
 
         return new $class;
     }
 
     /**
      * Returns storage(s) capabilities
      *
      * @return array Capabilities
      */
     public function capabilities()
     {
         $rcube   = rcube::get_instance();
         $backend = $this->get_backend();
         $caps    = array();
 
         // check support for upload progress
         if (($progress_sec = $rcube->config->get('upload_progress'))
             && ini_get('apc.rfc1867') && function_exists('apc_fetch')
         ) {
             $caps[file_storage::CAPS_PROGRESS_NAME] = ini_get('apc.rfc1867_name');
             $caps[file_storage::CAPS_PROGRESS_TIME] = $progress_sec;
         }
 
         // get capabilities of main storage module
         foreach ($backend->capabilities() as $name => $value) {
             // skip disabled capabilities
             if ($value !== false) {
                 $caps[$name] = $value;
             }
         }
 
         // Manticore support
         if ($manticore = $rcube->config->get('fileapi_manticore')) {
             $caps['MANTICORE'] = true;
         }
 
         // get capabilities of other drivers
         $drivers = $this->get_drivers(true);
 
         foreach ($drivers as $driver) {
             if ($driver != $backend) {
                 $title = $driver->title();
                 foreach ($driver->capabilities() as $name => $value) {
                     // skip disabled capabilities
                     if ($value !== false) {
                         $caps['MOUNTPOINTS'][$title][$name] = $value;
                     }
                 }
             }
         }
 
         return $caps;
     }
 
     /**
      * Get user name from user identifier (email address) using LDAP lookup
      *
      * @param string $email User identifier
      *
      * @return string User name
      */
     public function resolve_user($email)
     {
         $key = "user:$email";
 
         // @todo: Move this into drivers
         if ($this->icache[$key] === null
             && class_exists('kolab_storage', false)
             && ($ldap = kolab_storage::ldap())
         ) {
             $user = $ldap->get_user_record($email, $_SESSION['imap_host']);
 
             $this->icache[$key] = $user ?: false;
         }
 
         if ($this->icache[$key]) {
             return $this->icache[$key]['displayname'] ?: $this->icache[$key]['name'];
         }
     }
 
     /**
      * Return mimetypes list supported by built-in viewers
      *
      * @return array List of mimetypes
      */
     protected function supported_mimetypes()
     {
         $mimetypes = array();
         $dir       = __DIR__ . '/viewers';
 
         if ($handle = opendir($dir)) {
             while (false !== ($file = readdir($handle))) {
                 if (preg_match('/^([a-z0-9_]+)\.php$/i', $file, $matches)) {
                     include_once $dir . '/' . $file;
                     $class  = 'file_viewer_' . $matches[1];
                     $viewer = new $class($this);
 
                     $mimetypes = array_merge($mimetypes, $viewer->supported_mimetypes());
                 }
             }
             closedir($handle);
         }
 
         return $mimetypes;
     }
 
     /**
      * Encrypts data with current user password
      *
      * @param string $str A string to encrypt
      *
      * @return string Encrypted string (and base64-encoded)
      */
     public function encrypt($str)
     {
         $rcube = rcube::get_instance();
         $key   = $this->get_crypto_key();
 
         return $rcube->encrypt($str, $key, true);
     }
 
     /**
      * Decrypts data encrypted with encrypt() method
      *
      * @param string $str Encrypted string (base64-encoded)
      *
      * @return string Decrypted string
      */
     public function decrypt($str)
     {
         $rcube = rcube::get_instance();
         $key   = $this->get_crypto_key();
 
         return $rcube->decrypt($str, $key, true);
     }
 
     /**
      * Set encryption password
      */
     protected function get_crypto_key()
     {
         $key      = 'chwala_crypto_key';
         $rcube    = rcube::get_instance();
         $backend  = $this->get_backend();
         $user     = $backend->auth_info();
         $password = $user['password'] . $user['username'];
 
         // encryption password must be 24 characters, no less, no more
         if (($len = strlen($password)) > 24) {
             $password = substr($password, 0, 24);
         }
         else {
             $password = $password . substr($rcube->config->get('des_key'), 0, 24 - $len);
         }
 
         $rcube->config->set($key, $password);
 
         return $key;
     }
 }