diff --git a/plugins/kolab_folders/kolab_folders.php b/plugins/kolab_folders/kolab_folders.php
index 1ca29803..126ec7f9 100644
--- a/plugins/kolab_folders/kolab_folders.php
+++ b/plugins/kolab_folders/kolab_folders.php
@@ -72,6 +72,11 @@ class kolab_folders extends rcube_plugin
         // ACL plugin hooks
         $this->add_hook('acl_rights_simple', array($this, 'acl_rights_simple'));
         $this->add_hook('acl_rights_supported', array($this, 'acl_rights_supported'));
+
+        // Resolving other user folder names
+        $this->add_hook('render_mailboxlist', array($this, 'render_folderlist'));
+        $this->add_hook('render_folder_selector', array($this, 'render_folderlist'));
+        $this->add_hook('folders_list', array($this, 'render_folderlist'));
     }
 
     /**
@@ -709,6 +714,7 @@ class kolab_folders extends rcube_plugin
      * Static getter for default folder of the given type
      *
      * @param string $type Folder type
+     *
      * @return string Folder name
      */
     public static function default_folder($type)
@@ -781,4 +787,74 @@ class kolab_folders extends rcube_plugin
             );
         }
     }
+
+    /**
+     * Handler for various folders list widgets (hooks)
+     *
+     * @param array $args Hash array with hook parameters
+     *
+     * @return array Hash array with modified hook parameters
+     */
+    public function render_folderlist($args)
+    {
+        $storage  = $this->rc->get_storage();
+        $ns_other = $storage->get_namespace('other');
+        $is_fl    = $this->rc->plugins->is_processing('folders_list');
+
+        foreach ((array) $ns_other as $root) {
+            $delim  = $root[1];
+            $prefix = rtrim($root[0], $delim);
+            $length = strlen($prefix);
+
+            if (!$length) {
+                continue;
+            }
+
+            // folders_list hook mode
+            if ($is_fl) {
+                foreach ((array) $args['list'] as $folder_name => $folder) {
+                    if (strpos($folder_name, $root[0]) === 0 && !substr_count($folder_name, $root[1], $length+1)) {
+                        if ($name = $this->folder_id2username(substr($folder_name, $length+1))) {
+                            $old     = $args['list'][$folder_name]['display'];
+                            $content = $args['list'][$folder_name]['content'];
+
+                            $name    = rcube::Q($name);
+                            $content = str_replace(">$old<", ">$name<", $content);
+
+                            $args['list'][$folder_name]['display'] = $name;
+                            $args['list'][$folder_name]['content'] = $content;
+                        }
+                    }
+                }
+
+                // TODO: Re-sort the list
+            }
+            // render_* hooks mode
+            else if (!empty($args['list'][$prefix]) && !empty($args['list'][$prefix]['folders'])) {
+                $map = array();
+                foreach ($args['list'][$prefix]['folders'] as $folder_name => $folder) {
+                    if ($name = $this->folder_id2username($folder_name)) {
+                        $args['list'][$prefix]['folders'][$folder_name]['name'] = $name;
+                    }
+
+                    $map[$folder_name] = $name ?: $args['list'][$prefix]['folders'][$folder_name]['name'];
+                }
+
+                // Re-sort the list
+                uasort($map, 'strcoll');
+                $args['list'][$prefix]['folders'] = array_replace($map, $args['list'][$prefix]['folders']);
+            }
+        }
+
+        return $args;
+    }
+
+    /**
+     * Map other user (imap) folder identifier to user name
+     * @see kolab_storage::folder_id2user()
+     */
+    private static function folder_id2username($uid)
+    {
+        return kolab_storage::folder_id2user($uid, true);
+    }
 }
diff --git a/plugins/libkolab/config.inc.php.dist b/plugins/libkolab/config.inc.php.dist
index a2c15e8c..a4a7a7a6 100644
--- a/plugins/libkolab/config.inc.php.dist
+++ b/plugins/libkolab/config.inc.php.dist
@@ -64,6 +64,18 @@ $config['kolab_users_id_attrib'] = null;
 // Use these attributes when searching users in LDAP
 $config['kolab_users_search_attrib'] = array('cn','mail','alias');
 
+// Which property of the LDAP user record to use as a display name.
+// Defaults to the 'kolab_auth_name' configuration option.
+$config['kolab_users_name_field'] = null;
+
+// Type of cache for uid-to-user map. Supported: 'db', 'apc', 'memcache' and 'memcached'.
+// Note: This stores only other user folder identifier to user attributes map.
+$config['kolab_users_cache'] = null;
+
+// lifetime of shared folder mapping cache
+// possible units: s, m, h, d, w
+$config['kolab_users_cache_ttl'] = '10d';
+
 // JSON-RPC endpoint configuration of the Bonnie web service providing historic data for groupware objects
 $config['kolab_bonnie_api'] = array(
     'uri'    => 'https://<kolab-hostname>:8080/api/rpc',
diff --git a/plugins/libkolab/lib/kolab_storage.php b/plugins/libkolab/lib/kolab_storage.php
index 39d6ff11..61a2fa74 100644
--- a/plugins/libkolab/lib/kolab_storage.php
+++ b/plugins/libkolab/lib/kolab_storage.php
@@ -46,12 +46,14 @@ class kolab_storage
     private static $ready = false;
     private static $with_tempsubs = true;
     private static $subscriptions;
+    private static $ldapcache = array();
     private static $typedata = array();
     private static $states;
     private static $config;
     private static $imap;
     private static $ldap;
 
+
     // Default folder names
     private static $default_folders = array(
         'event'         => 'Calendar',
@@ -354,7 +356,6 @@ class kolab_storage
         return '';
     }
 
-
     /**
      * Deletes IMAP folder
      *
@@ -421,7 +422,6 @@ class kolab_storage
         return false;
     }
 
-
     /**
      * Renames IMAP folder
      *
@@ -457,7 +457,6 @@ class kolab_storage
         return $success;
     }
 
-
     /**
      * Rename or Create a new IMAP folder.
      *
@@ -552,7 +551,6 @@ class kolab_storage
         return $result ? $folder : false;
     }
 
-
     /**
      * Getter for human-readable name of Kolab object (folder)
      * with kolab_custom_display_names support.
@@ -637,20 +635,18 @@ class kolab_storage
         if (!$found && !empty($namespace['other'])) {
             foreach ($namespace['other'] as $ns) {
                 if (strlen($ns[0]) && strpos($folder, $ns[0]) === 0) {
-                    // remove namespace prefix
+                    // remove namespace prefix and extract username
                     $folder = substr($folder, strlen($ns[0]));
                     $delim  = $ns[1];
-                    // get username
-                    $pos    = strpos($folder, $delim);
-                    if ($pos) {
-                        $prefix = '('.substr($folder, 0, $pos).')';
-                        $folder = substr($folder, $pos+1);
-                    }
-                    else {
-                        $prefix = '('.$folder.')';
-                        $folder = '';
-                    }
 
+                    // get username part and map it to user name
+                    $pos = strpos($folder, $delim);
+                    $fid = $pos ? substr($folder, 0, $pos) : $folder;
+                    $fid = self::folder_id2user($fid, true);
+                    $fid = str_replace($delim, '', $fid);
+
+                    $prefix = "($fid)";
+                    $folder = $pos ? substr($folder, $pos + 1) : '';
                     $found  = true;
                     $folder_ns = 'other';
                     break;
@@ -729,7 +725,6 @@ class kolab_storage
         return $name;
     }
 
-
     /**
      * Creates a SELECT field with folders list
      *
@@ -812,7 +807,6 @@ class kolab_storage
         return $select;
     }
 
-
     /**
      * Returns a list of folder names
      *
@@ -976,7 +970,6 @@ class kolab_storage
         return $folders;
     }
 
-
     /**
      * Sort the given list of kolab folders by namespace/name
      *
@@ -1006,7 +999,6 @@ class kolab_storage
         return $out;
     }
 
-
     /**
      * Check the folder tree and add the missing parents as virtual folders
      *
@@ -1082,7 +1074,6 @@ class kolab_storage
         return $_folders;
     }
 
-
     /**
      * Returns folder types indexed by folder name
      *
@@ -1149,7 +1140,6 @@ class kolab_storage
         return self::$typedata[$prefix];
     }
 
-
     /**
      * Callback for array_map to select the correct annotation value
      */
@@ -1165,7 +1155,6 @@ class kolab_storage
         return null;
     }
 
-
     /**
      * Returns type of IMAP folder
      *
@@ -1197,7 +1186,6 @@ class kolab_storage
         return 'mail';
     }
 
-
     /**
      * Sets folder content-type.
      *
@@ -1220,7 +1208,6 @@ class kolab_storage
         return $success;
     }
 
-
     /**
      * Check subscription status of this folder
      *
@@ -1242,7 +1229,6 @@ class kolab_storage
             ($temp && in_array($folder, (array)$_SESSION['kolab_subscribed_folders']));
     }
 
-
     /**
      * Change subscription status of this folder
      *
@@ -1273,7 +1259,6 @@ class kolab_storage
         return false;
     }
 
-
     /**
      * Change subscription status of this folder
      *
@@ -1301,7 +1286,6 @@ class kolab_storage
         return false;
     }
 
-
     /**
      * Check activation status of this folder
      *
@@ -1316,7 +1300,6 @@ class kolab_storage
         return in_array($folder, $active_folders);
     }
 
-
     /**
      * Change activation status of this folder
      *
@@ -1331,7 +1314,6 @@ class kolab_storage
         return self::set_state($folder, true);
     }
 
-
     /**
      * Change activation status of this folder
      *
@@ -1347,7 +1329,6 @@ class kolab_storage
         return self::set_state($folder, false);
     }
 
-
     /**
      * Return list of active folders
      */
@@ -1379,7 +1360,6 @@ class kolab_storage
         return self::$states;
     }
 
-
     /**
      * Update list of active folders
      */
@@ -1504,7 +1484,6 @@ class kolab_storage
         }
     }
 
-
     /**
      *
      * @param mixed   $query    Search value (or array of field => value pairs)
@@ -1544,7 +1523,6 @@ class kolab_storage
         return $results;
     }
 
-
     /**
      * Returns a list of IMAP folders shared by the given user
      *
@@ -1584,7 +1562,6 @@ class kolab_storage
         return $folders;
     }
 
-
     /**
      * Get a list of (virtual) top-level folders from the other users namespace
      *
@@ -1635,7 +1612,6 @@ class kolab_storage
         return $folders;
     }
 
-
     /**
      * Handler for user_delete plugin hooks
      *
@@ -1673,4 +1649,79 @@ class kolab_storage
             return $metadata[$folder];
         }
     }
+
+    /**
+     * Get user attributes for specified other user (imap) folder identifier.
+     * Note: This uses LDAP config/code from kolab_auth.
+     *
+     * @param string $folder_id Folder name w/o path (imap user identifier)
+     * @param bool   $as_string Return configured display name attribute value
+     *
+     * @return array User attributes
+     * @see self::ldap()
+     */
+    public static function folder_id2user($folder_id, $as_string = false)
+    {
+        static $domain, $cache, $name_attr;
+
+        $rcube = rcube::get_instance();
+
+        if ($domain === null) {
+            list(, $domain) = explode('@', $rcube->get_user_name());
+        }
+
+        if ($name_attr === null) {
+            $name_attr = (array) (self::$config->get('kolab_users_name_field', self::$config->get('kolab_auth_name')) ?: 'name');
+        }
+
+        $token = $folder_id;
+        if ($domain && strpos($find, '@') === false) {
+            $token .= '@' . $domain;
+        }
+
+        if ($cache === null) {
+            $cache = $rcube->get_cache_shared('kolab_users') ?: false;
+        }
+
+        // use value cached in memory for repeated lookups
+        if (!$cache && array_key_exists($token, self::$ldapcache)) {
+            $user = self::$ldapcache[$token];
+        }
+
+        if (empty($user) && $cache) {
+            $user = $cache->get($token);
+        }
+
+        if (empty($user) && ($ldap = kolab_storage::ldap())) {
+            $user = $ldap->get_user_record($token, $_SESSION['imap_host']);
+
+            if (!empty($user)) {
+                $keys = array('displayname', 'name', 'mail'); // supported keys
+                $user = array_intersect_key($user, array_flip($keys));
+
+                if (!empty($user)) {
+                    if ($cache) {
+                        $cache->set($token, $user);
+                    }
+                    else {
+                        self::$ldapcache[$token] = $user;
+                    }
+                }
+            }
+        }
+
+        if (!empty($user)) {
+            if ($as_string) {
+                foreach ($name_attr as $attr) {
+                    if ($name = $user[$attr]) {
+                        return $name;
+                    }
+                }
+
+                return $user['displayname'] ?: $user['name'];
+            }
+
+            return $user;
+        }
+    }
 }
diff --git a/plugins/libkolab/lib/kolab_storage_folder_user.php b/plugins/libkolab/lib/kolab_storage_folder_user.php
index ec751fdb..707ce817 100644
--- a/plugins/libkolab/lib/kolab_storage_folder_user.php
+++ b/plugins/libkolab/lib/kolab_storage_folder_user.php
@@ -23,8 +23,6 @@
  */
 class kolab_storage_folder_user extends kolab_storage_folder_virtual
 {
-    protected static $ldapcache = array();
-
     public $ldaprec;
     public $type;
 
@@ -36,21 +34,13 @@ class kolab_storage_folder_user extends kolab_storage_folder_virtual
         parent::__construct($name, kolab_storage::object_prettyname($name), 'other', $parent);
 
         if (!empty($ldaprec)) {
-            self::$ldapcache[$name] = $this->ldaprec = $ldaprec;
+            $this->ldaprec = $ldaprec;
         }
-        // use value cached in memory for repeated lookups
-        else if (array_key_exists($name, self::$ldapcache)) {
-            $this->ldaprec = self::$ldapcache[$name];
-        }
-        // lookup user in LDAP and set $this->ldaprec
-        else if ($ldap = kolab_storage::ldap()) {
-            // get domain from current user
-            list(,$domain) = explode('@', rcube::get_instance()->get_user_name());
-            $this->ldaprec = $ldap->get_user_record(parent::get_foldername($this->name) . '@' . $domain, $_SESSION['imap_host']);
+        else {
+            $this->ldaprec = kolab_storage::folder_id2user(parent::get_foldername($this->name));
             if (!empty($this->ldaprec)) {
                 $this->ldaprec['kolabtargetfolder'] = $name;
             }
-            self::$ldapcache[$name] = $this->ldaprec;
         }
     }