diff --git a/plugins/libkolab/lib/kolab_storage.php b/plugins/libkolab/lib/kolab_storage.php
index c9a90e7c..65326248 100644
--- a/plugins/libkolab/lib/kolab_storage.php
+++ b/plugins/libkolab/lib/kolab_storage.php
@@ -1018,7 +1018,7 @@ class kolab_storage
             $folder->children = array();  // reset list
 
             // skip top folders or ones with a custom displayname
-            if (count($path) < 1 || kolab_storage::custom_displayname($folder->name)) {
+            if (count($path) < 1 || $folder->get_custom_displayname()) {
                 $tree->children[] = $folder;
             }
             else {
diff --git a/plugins/libkolab/lib/kolab_storage_folder_api.php b/plugins/libkolab/lib/kolab_storage_folder_api.php
index 32e839cf..3aa7c45b 100644
--- a/plugins/libkolab/lib/kolab_storage_folder_api.php
+++ b/plugins/libkolab/lib/kolab_storage_folder_api.php
@@ -146,6 +146,20 @@ abstract class kolab_storage_folder_api
      * @return string Folder name
      */
     public function get_name()
+    {
+        if ($name = $this->get_custom_displayname()) {
+            return $name;
+        }
+
+        return kolab_storage::object_prettyname($this->name);
+    }
+
+    /**
+     * Get the custom display name of this folder
+     *
+     * @return string Folder custom name
+     */
+    public function get_custom_displayname()
     {
         $rcmail = rcube::get_instance();
 
@@ -156,12 +170,11 @@ abstract class kolab_storage_folder_api
             if ($name = $metadata[kolab_storage::NAME_KEY_PRIVATE]) {
                 return $name;
             }
+
             if ($name = $metadata[kolab_storage::NAME_KEY_SHARED]) {
                 return $name;
             }
         }
-
-        return kolab_storage::object_prettyname($this->name);
     }
 
     /**