diff --git a/plugins/kolab_addressbook/config.inc.php.dist b/plugins/kolab_addressbook/config.inc.php.dist
index ba8f60d1..bf4dc1d5 100644
--- a/plugins/kolab_addressbook/config.inc.php.dist
+++ b/plugins/kolab_addressbook/config.inc.php.dist
@@ -1,5 +1,10 @@
 <?php
 
+// Backend type (kolab, carddav)
+$config['kolab_addressbook_driver'] = "kolab";
+
+// CalDAV server location (required when kolab_addressbook_driver = carddav)
+$config['kolab_addressbook_carddav_server'] = "http://localhost";
 
 // This option allows to set addressbooks priority or to disable some
 // of them. Disabled addressbooks will be not shown in the UI. Default: 0.
@@ -15,7 +20,8 @@ $config['kolab_addressbook_prio'] = 0;
 // %u - Current webmail user name
 // %n - Folder name
 // %i - Folder UUID
-// $config['kolab_addressbook_carddav_url'] = 'http://%h/iRony/addressbooks/%u/%i';
+// For example: 'http://%h/iRony/addressbooks/%u/%i'
+$config['kolab_addressbook_carddav_url'] = null;
 
 // Name of LDAP addressbook (a key in ldap_public configuration array) for which
 // the CardDAV URI will be displayed if kolab_addressbook_carddav_url is set.
@@ -31,5 +37,3 @@ $config['kolab_addressbook_prio'] = 0;
 // ignore these properties and allow modifications which then result in sync errors because the server
 // denies such updates.
 $config['kolab_addressbook_carddav_ldap'] = '';
-
-?>
diff --git a/plugins/kolab_addressbook/kolab_addressbook.php b/plugins/kolab_addressbook/kolab_addressbook.php
index efbf74c8..a5c6e446 100644
--- a/plugins/kolab_addressbook/kolab_addressbook.php
+++ b/plugins/kolab_addressbook/kolab_addressbook.php
@@ -31,12 +31,13 @@ class kolab_addressbook extends rcube_plugin
 {
     public $task = '?(?!logout).*';
 
+    public $driver;
+    public $bonnie_api = false;
+
     private $sources;
-    private $folders;
     private $rc;
     private $ui;
-
-    public $bonnie_api = false;
+    private $driver_class;
 
     const GLOBAL_FIRST = 0;
     const PERSONAL_FIRST = 1;
@@ -53,8 +54,11 @@ class kolab_addressbook extends rcube_plugin
         // load required plugin
         $this->require_plugin('libkolab');
 
-        $driver = $this->rc->config->get('kolab_addressbook_driver') ?: 'kolab';
-        require_once(dirname(__FILE__) . '/lib/rcube_' . $driver . '_contacts.php');
+        $this->load_config();
+
+        $this->driver       = $this->rc->config->get('kolab_addressbook_driver') ?: 'kolab';
+        $this->driver_class = 'rcube_' . $this->driver . '_contacts';
+        require_once(dirname(__FILE__) . '/lib/' . $this->driver_class . '.php');
 
         // register hooks
         $this->add_hook('addressbooks_list', array($this, 'address_sources'));
@@ -82,7 +86,6 @@ class kolab_addressbook extends rcube_plugin
 
             // Load UI elements
             if ($this->api->output->type == 'html') {
-                $this->load_config();
                 require_once($this->home . '/lib/kolab_addressbook_ui.php');
                 $this->ui = new kolab_addressbook_ui($this);
 
@@ -104,9 +107,11 @@ class kolab_addressbook extends rcube_plugin
             $this->add_hook('preferences_save', array($this, 'prefs_save'));
         }
 
-        $this->add_hook('folder_delete', array($this, 'prefs_folder_delete'));
-        $this->add_hook('folder_rename', array($this, 'prefs_folder_rename'));
-        $this->add_hook('folder_update', array($this, 'prefs_folder_update'));
+        if ($this->driver == 'kolab') {
+            $this->add_hook('folder_delete', array($this, 'prefs_folder_delete'));
+            $this->add_hook('folder_rename', array($this, 'prefs_folder_rename'));
+            $this->add_hook('folder_update', array($this, 'prefs_folder_update'));
+        }
     }
 
     /**
@@ -212,10 +217,22 @@ class kolab_addressbook extends rcube_plugin
             $out .= $this->addressbook_list_item($id, $source, $jsdata) . '</li>';
         }
 
+        $filter  = function($source) { return !empty($source['kolab']) && empty($source['hidden']); };
+        $folders = array_filter($sources, $filter);
+
         // render a hierarchical list of kolab contact folders
-        kolab_storage::folder_hierarchy($this->folders, $tree);
-        if ($tree && !empty($tree->children)) {
-            $out .= $this->folder_tree_html($tree, $sources, $jsdata);
+        // TODO: Move this to the drivers
+        if ($this->driver == 'kolab') {
+            kolab_storage::folder_hierarchy($folders, $tree);
+            if ($tree && !empty($tree->children)) {
+                $out .= $this->folder_tree_html($tree, $sources, $jsdata);
+            }
+        }
+        else {
+            foreach ($folders as $j => $source) {
+                $id = strval(strlen($source['id']) ? $source['id'] : $j);
+                $out .= $this->addressbook_list_item($id, $source, $jsdata) . '</li>';
+            }
         }
 
         $this->rc->output->set_env('contactgroups', array_filter($jsdata, function($src){ return $src['type'] == 'group'; }));
@@ -303,7 +320,7 @@ class kolab_addressbook extends rcube_plugin
                 ), $name)
         );
 
-        if (isset($source['subscribed'])) {
+        if ($this->driver == 'kolab' && isset($source['subscribed'])) {
             $inner .= html::span(array(
                 'class' => 'subscribed',
                 'title' => $this->gettext('foldersubscribe'),
@@ -396,7 +413,6 @@ class kolab_addressbook extends rcube_plugin
         return $args;
     }
 
-
     /**
      * Getter for the rcube_addressbook instance
      *
@@ -407,16 +423,8 @@ class kolab_addressbook extends rcube_plugin
     public function get_address_book($p)
     {
         if ($p['id']) {
-            $id     = kolab_storage::id_decode($p['id']);
-            $folder = kolab_storage::get_folder($id);
-
-            // try with unencoded (old-style) identifier
-            if ((!$folder || $folder->type != 'contact') && $id != $p['id']) {
-                $folder = kolab_storage::get_folder($p['id']);
-            }
-
-            if ($folder && $folder->type == 'contact') {
-                $p['instance'] = new rcube_kolab_contacts($folder->name);
+            if ($source = $this->driver_class::get_address_book($p['id'])) {
+                $p['instance'] = $source;
 
                 // flag source as writeable if 'i' right is given
                 if ($p['writeable'] && $this->rc->action == 'save' && strpos($p['instance']->rights, 'i') !== false) {
@@ -431,57 +439,33 @@ class kolab_addressbook extends rcube_plugin
         return $p;
     }
 
-
+    /**
+     * List addressbook sources list
+     */
     private function _list_sources()
     {
         // already read sources
-        if (isset($this->sources))
+        if (isset($this->sources)) {
             return $this->sources;
+        }
 
-        kolab_storage::$encode_ids = true;
-        $this->sources = array();
-        $this->folders = array();
+        $this->sources = [];
 
         $abook_prio = $this->addressbook_prio();
 
         // Personal address source(s) disabled?
-        if ($abook_prio == self::GLOBAL_ONLY) {
+        if ($abook_prio == kolab_addressbook::GLOBAL_ONLY) {
             return $this->sources;
         }
 
         // get all folders that have "contact" type
-        $folders = kolab_storage::sort_folders(kolab_storage::get_folders('contact'));
-
-        if (PEAR::isError($folders)) {
-            rcube::raise_error(array(
-              'code' => 600, 'type' => 'php',
-              'file' => __FILE__, 'line' => __LINE__,
-              'message' => "Failed to list contact folders from Kolab server:" . $folders->getMessage()),
-            true, false);
-        }
-        else {
-            // we need at least one folder to prevent from errors in Roundcube core
-            // when there's also no sql nor ldap addressbook (Bug #2086)
-            if (empty($folders)) {
-                if ($folder = kolab_storage::create_default_folder('contact')) {
-                    $folders = array(new kolab_storage_folder($folder, 'contact'));
-                }
-            }
-
-            // convert to UTF8 and sort
-            foreach ($folders as $folder) {
-                // create instance of rcube_contacts
-                $abook_id = $folder->id;
-                $abook = new rcube_kolab_contacts($folder->name);
-                $this->sources[$abook_id] = $abook;
-                $this->folders[$abook_id] = $folder;
-            }
+        foreach ($this->driver_class::list_folders() as $id => $source) {
+            $this->sources[$id] = $source;
         }
 
         return $this->sources;
     }
 
-
     /**
      * Plugin hook called before rendering the contact form or detail view
      *
@@ -801,17 +785,17 @@ class kolab_addressbook extends rcube_plugin
      */
     private function _sort_form_fields($contents, $source)
     {
-      $block = array();
+        $block = [];
 
-      foreach (array_keys($source->coltypes) as $col) {
-          if (isset($contents[$col]))
-              $block[$col] = $contents[$col];
-      }
+        foreach (array_keys($source->coltypes) as $col) {
+            if (isset($contents[$col])) {
+                $block[$col] = $contents[$col];
+            }
+        }
 
-      return $block;
+        return $block;
     }
 
-
     /**
      * Handler for user preferences form (preferences_list hook)
      *
@@ -959,9 +943,9 @@ class kolab_addressbook extends rcube_plugin
      */
     public function book_search()
     {
-        $results = array();
-        $query = rcube_utils::get_input_value('q', rcube_utils::INPUT_GPC);
-        $source = rcube_utils::get_input_value('source', rcube_utils::INPUT_GPC);
+        $results = [];
+        $query   = rcube_utils::get_input_value('q', rcube_utils::INPUT_GPC);
+        $source  = rcube_utils::get_input_value('source', rcube_utils::INPUT_GPC);
 
         kolab_storage::$encode_ids = true;
         $search_more_results = false;
@@ -1109,12 +1093,6 @@ class kolab_addressbook extends rcube_plugin
      */
     private function addressbook_prio()
     {
-        // Load configuration
-        if (!$this->config_loaded) {
-            $this->load_config();
-            $this->config_loaded = true;
-        }
-
         $abook_prio = (int) $this->rc->config->get('kolab_addressbook_prio');
 
         // Make sure any global addressbooks are defined
diff --git a/plugins/kolab_addressbook/lib/kolab_addressbook_ui.php b/plugins/kolab_addressbook/lib/kolab_addressbook_ui.php
index 710b5562..b6bad178 100644
--- a/plugins/kolab_addressbook/lib/kolab_addressbook_ui.php
+++ b/plugins/kolab_addressbook/lib/kolab_addressbook_ui.php
@@ -54,6 +54,10 @@ class kolab_addressbook_ui
             // Include stylesheet (for directorylist)
             $this->plugin->include_stylesheet($this->plugin->local_skin_path().'/kolab_addressbook.css');
 
+            if ($this->plugin->driver != 'kolab') {
+                return;
+            }
+
             // include kolab folderlist widget if available
             if (in_array('libkolab', $this->plugin->api->loaded_plugins())) {
                 $this->plugin->api->include_script('libkolab/libkolab.js');
@@ -66,20 +70,20 @@ class kolab_addressbook_ui
             $idx     = 0;
 
             if ($dav_url = $this->rc->config->get('kolab_addressbook_carddav_url')) {
-              $options[] = 'book-showurl';
-              $this->rc->output->set_env('kolab_addressbook_carddav_url', true);
+                $options[] = 'book-showurl';
+                $this->rc->output->set_env('kolab_addressbook_carddav_url', true);
 
-              // set CardDAV URI for specified ldap addressbook
-              if ($ldap_abook = $this->rc->config->get('kolab_addressbook_carddav_ldap')) {
-                $dav_ldap_url = strtr($dav_url, array(
-                    '%h' => $_SERVER['HTTP_HOST'],
-                    '%u' => urlencode($this->rc->get_user_name()),
-                    '%i' => 'ldap-directory',
-                    '%n' => '',
-                ));
-                $this->rc->output->set_env('kolab_addressbook_carddav_ldap', $ldap_abook);
-                $this->rc->output->set_env('kolab_addressbook_carddav_ldap_url', $dav_ldap_url);
-              }
+                // set CardDAV URI for specified ldap addressbook
+                if ($ldap_abook = $this->rc->config->get('kolab_addressbook_carddav_ldap')) {
+                    $dav_ldap_url = strtr($dav_url, array(
+                        '%h' => $_SERVER['HTTP_HOST'],
+                        '%u' => urlencode($this->rc->get_user_name()),
+                        '%i' => 'ldap-directory',
+                        '%n' => '',
+                    ));
+                    $this->rc->output->set_env('kolab_addressbook_carddav_ldap', $ldap_abook);
+                    $this->rc->output->set_env('kolab_addressbook_carddav_ldap_url', $dav_ldap_url);
+                }
             }
 
             foreach ($options as $command) {
diff --git a/plugins/kolab_addressbook/lib/rcube_kolab_contacts.php b/plugins/kolab_addressbook/lib/rcube_kolab_contacts.php
index 1f9ac291..be1a2b02 100644
--- a/plugins/kolab_addressbook/lib/rcube_kolab_contacts.php
+++ b/plugins/kolab_addressbook/lib/rcube_kolab_contacts.php
@@ -312,6 +312,64 @@ class rcube_kolab_contacts extends rcube_addressbook
         $this->filter = null;
     }
 
+    /**
+     * List addressbook sources (folders)
+     */
+    public static function list_folders()
+    {
+        kolab_storage::$encode_ids = true;
+
+        // get all folders that have "contact" type
+        $folders = kolab_storage::sort_folders(kolab_storage::get_folders('contact'));
+
+        if (PEAR::isError($folders)) {
+            rcube::raise_error([
+                    'code' => 600, 'file' => __FILE__, 'line' => __LINE__,
+                    'message' => "Failed to list contact folders from Kolab server:" . $folders->getMessage()
+                ],
+                true, false);
+
+            return [];
+        }
+
+        // we need at least one folder to prevent from errors in Roundcube core
+        // when there's also no sql nor ldap addressbook (Bug #2086)
+        if (empty($folders)) {
+            if ($folder = kolab_storage::create_default_folder('contact')) {
+                $folders = [new kolab_storage_folder($folder, 'contact')];
+            }
+        }
+
+        $sources = [];
+        foreach ($folders as $folder) {
+            $sources[$folder->id] = new rcube_kolab_contacts($folder->name);
+        }
+
+        return $sources;
+    }
+
+    /**
+     * Getter for the rcube_addressbook instance
+     *
+     * @param string $id Addressbook (folder) ID
+     *
+     * @return ?rcube_kolab_contacts
+     */
+    public static function get_address_book($id)
+    {
+        $folderId = kolab_storage::id_decode($id);
+        $folder   = kolab_storage::get_folder($folderId);
+
+        // try with unencoded (old-style) identifier
+        if ((!$folder || $folder->type != 'contact') && $folderId != $id) {
+            $folder = kolab_storage::get_folder($id);
+        }
+
+        if ($folder && $folder->type == 'contact') {
+            return new rcube_kolab_contacts($folder->name);
+        }
+    }
+
     /**
      * List all active contact groups of this source
      *
diff --git a/plugins/libkolab/lib/kolab_dav_client.php b/plugins/libkolab/lib/kolab_dav_client.php
index d9ae88da..e6962f53 100644
--- a/plugins/libkolab/lib/kolab_dav_client.php
+++ b/plugins/libkolab/lib/kolab_dav_client.php
@@ -73,7 +73,6 @@ class kolab_dav_client
         }
 
         try {
-
             $request = $this->initRequest($this->url . $path, $method, $request_config);
 
             $request->setAuth($this->user, $this->password);
@@ -135,7 +134,8 @@ class kolab_dav_client
                 . '</d:prop>'
             . '</d:propfind>';
 
-        $response = $this->request('/' . $roots[$component], 'PROPFIND', $body);
+        // Note: Cyrus CardDAV service requires Depth:1 (CalDAV works without it)
+        $response = $this->request('/' . $roots[$component], 'PROPFIND', $body, ['Depth' => 1, 'Prefer' => 'return-minimal']);
 
         $elements = $response->getElementsByTagName('response');
 
@@ -150,10 +150,22 @@ class kolab_dav_client
             $principal_href = substr($principal_href, strlen($path));
         }
 
+        $homes = [
+            'VEVENT' => 'calendar-home-set',
+            'VTODO' => 'calendar-home-set',
+            'VCARD' => 'addressbook-home-set',
+        ];
+
+        $ns = [
+            'VEVENT' => 'caldav',
+            'VTODO' => 'caldav',
+            'VCARD' => 'carddav',
+        ];
+
         $body = '<?xml version="1.0" encoding="utf-8"?>'
-            . '<d:propfind xmlns:d="DAV:" xmlns:c="urn:ietf:params:xml:ns:caldav">'
+            . '<d:propfind xmlns:d="DAV:" xmlns:c="urn:ietf:params:xml:ns:' . $ns[$component] . '">'
                 . '<d:prop>'
-                    . '<c:calendar-home-set />'
+                    . '<c:' . $homes[$component] . ' />'
                 . '</d:prop>'
             . '</d:propfind>';
 
@@ -178,28 +190,41 @@ class kolab_dav_client
             $root_href = '/' . $roots[$component] . '/' . rawurlencode($this->user);
         }
 
+        if ($component == 'VCARD') {
+            $add_ns = '';
+            $add_props = '';
+        }
+        else {
+            $add_ns = ' xmlns:c="urn:ietf:params:xml:ns:caldav" xmlns:a="http://apple.com/ns/ical/"';
+            $add_props = '<c:supported-calendar-component-set /><a:calendar-color />';
+        }
+
         $body = '<?xml version="1.0" encoding="utf-8"?>'
-            . '<d:propfind xmlns:d="DAV:" xmlns:cs="http://calendarserver.org/ns/" xmlns:c="urn:ietf:params:xml:ns:caldav" xmlns:a="http://apple.com/ns/ical/">'
+            . '<d:propfind xmlns:d="DAV:" xmlns:cs="http://calendarserver.org/ns/"' . $add_ns . '>'
                 . '<d:prop>'
                     . '<d:resourcetype />'
                     . '<d:displayname />'
+                    // . '<d:sync-token />'
                     . '<cs:getctag />'
-                    . '<c:supported-calendar-component-set />'
-                    . '<a:calendar-color />'
+                    . $add_props
                 . '</d:prop>'
             . '</d:propfind>';
 
-        $response = $this->request($root_href, 'PROPFIND', $body);
+        // Note: Cyrus CardDAV service requires Depth:1 (CalDAV works without it)
+        $response = $this->request($root_href, 'PROPFIND', $body, ['Depth' => 1, 'Prefer' => 'return-minimal']);
 
         if (empty($response)) {
             return false;
         }
 
         $folders = [];
-
         foreach ($response->getElementsByTagName('response') as $element) {
             $folder = $this->getFolderPropertiesFromResponse($element);
-            if ($folder['type'] === $component) {
+
+            // Note: Addressbooks don't have 'type' specified
+            if (($component == 'VCARD' && in_array('addressbook', $folder['resource_type']))
+                || $folder['type'] === $component
+            ) {
                 $folders[] = $folder;
             }
         }
@@ -210,9 +235,17 @@ class kolab_dav_client
     /**
      * Create a DAV object in a folder
      */
-    public function create($location, $content)
+    public function create($location, $content, $component = 'VEVENT')
     {
-        $response = $this->request($location, 'PUT', $content, ['Content-Type' => 'text/calendar; charset=utf-8']);
+        $ctype = [
+            'VEVENT' => 'text/calendar',
+            'VTODO' => 'text/calendar',
+            'VCARD' => 'text/vcard',
+        ];
+
+        $headers = ['Content-Type' => $ctype[$component] . '; charset=utf-8'];
+
+        $response = $this->request($location, 'PUT', $content, $headers);
 
         if ($response !== false) {
             $etag = $this->responseHeaders['etag'];
@@ -230,9 +263,9 @@ class kolab_dav_client
     /**
      * Update a DAV object in a folder
      */
-    public function update($location, $content)
+    public function update($location, $content, $component = 'VEVENT')
     {
-        return $this->create($location, $content);
+        return $this->create($location, $content, $component);
     }
 
     /**
diff --git a/plugins/libkolab/lib/kolab_storage_dav.php b/plugins/libkolab/lib/kolab_storage_dav.php
index ce064178..15295cfb 100644
--- a/plugins/libkolab/lib/kolab_storage_dav.php
+++ b/plugins/libkolab/lib/kolab_storage_dav.php
@@ -100,14 +100,18 @@ class kolab_storage_dav
     /**
      * Getter for a specific storage folder
      *
-     * @param string Folder to access
-     * @param string Expected folder type
+     * @param string $id   Folder to access
+     * @param string $type Expected folder type
      *
-     * @return object kolab_storage_folder The folder object
+     * @return ?object kolab_storage_folder The folder object
      */
-    public function get_folder($folder, $type = null)
+    public function get_folder($id, $type = null)
     {
-        // TODO
+        foreach ($this->get_folders($type) as $folder) {
+            if ($folder->id == $id) {
+                return $folder;
+            }
+        }
     }
 
     /**
diff --git a/plugins/libkolab/lib/kolab_storage_dav_cache.php b/plugins/libkolab/lib/kolab_storage_dav_cache.php
index 837783b5..b089b170 100644
--- a/plugins/libkolab/lib/kolab_storage_dav_cache.php
+++ b/plugins/libkolab/lib/kolab_storage_dav_cache.php
@@ -319,8 +319,8 @@ class kolab_storage_dav_cache extends kolab_storage_cache
 
             $sql_data              = $this->_serialize($object);
             $sql_data['folder_id'] = $this->folder_id;
-            $sql_data['uid']       = $object['uid'];
-            $sql_data['etag']      = $object['etag'];
+            $sql_data['uid']       = rcube_charset::clean($object['uid']);
+            $sql_data['etag']      = rcube_charset::clean($object['etag']);
 
             $args = [];
             $cols = ['folder_id', 'uid', 'etag', 'changed', 'data', 'tags', 'words'];
@@ -524,8 +524,15 @@ class kolab_storage_dav_cache extends kolab_storage_cache
             // In Oracle we can't put long data inline, others we don't support yet
             if (strpos($this->db->db_provider, 'mysql') !== 0) {
                 $extra_args = [];
-                $params = [$this->folder_id, $object['uid'], $object['etag'], $sql_data['changed'],
-                    $sql_data['data'], $sql_data['tags'], $sql_data['words']];
+                $params = [
+                    $this->folder_id,
+                    rcube_charset::clean($object['uid']),
+                    rcube_charset::clean($object['etag']),
+                    $sql_data['changed'],
+                    $sql_data['data'],
+                    $sql_data['tags'],
+                    $sql_data['words']
+                ];
 
                 foreach ($this->extra_cols as $col) {
                     $params[] = $sql_data[$col];
@@ -552,8 +559,8 @@ class kolab_storage_dav_cache extends kolab_storage_cache
 
             $values = array(
                 $this->db->quote($this->folder_id),
-                $this->db->quote($object['uid']),
-                $this->db->quote($object['etag']),
+                $this->db->quote(rcube_charset::clean($object['uid'])),
+                $this->db->quote(rcube_charset::clean($object['etag'])),
                 $this->db->now(),
                 $this->db->quote($sql_data['changed']),
                 $this->db->quote($sql_data['data']),
diff --git a/plugins/libkolab/lib/kolab_storage_dav_cache_contact.php b/plugins/libkolab/lib/kolab_storage_dav_cache_contact.php
index 66d2b830..0ca118dd 100644
--- a/plugins/libkolab/lib/kolab_storage_dav_cache_contact.php
+++ b/plugins/libkolab/lib/kolab_storage_dav_cache_contact.php
@@ -21,12 +21,12 @@
  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  */
 
-class kolab_storage_cache_contact extends kolab_storage_cache
+class kolab_storage_dav_cache_contact extends kolab_storage_dav_cache
 {
     protected $extra_cols_max = 255;
     protected $extra_cols     = ['type', 'name', 'firstname', 'surname', 'email'];
     protected $data_props     = ['type', 'name', 'firstname', 'middlename', 'prefix', 'suffix', 'surname', 'email', 'organization', 'member'];
-    protected $fulltext_cols  = ['name', 'firstname', 'surname', 'middlename', 'email:address'];
+    protected $fulltext_cols  = ['name', 'firstname', 'surname', 'middlename', 'email'];
 
     /**
      * Helper method to convert the given Kolab object into a dataset to be written to cache
@@ -36,20 +36,20 @@ class kolab_storage_cache_contact extends kolab_storage_cache
     protected function _serialize($object)
     {
         $sql_data = parent::_serialize($object);
-        $sql_data['type'] = $object['_type'];
+        $sql_data['type'] = $object['_type'] ?: 'contact';
 
         // columns for sorting
         $sql_data['name']      = rcube_charset::clean($object['name'] . $object['prefix']);
         $sql_data['firstname'] = rcube_charset::clean($object['firstname'] . $object['middlename'] . $object['surname']);
         $sql_data['surname']   = rcube_charset::clean($object['surname']   . $object['firstname']  . $object['middlename']);
-        $sql_data['email']     = rcube_charset::clean(is_array($object['email']) ? $object['email'][0] : $object['email']);
+        $sql_data['email']     = '';
 
-        if (is_array($sql_data['email'])) {
-            $sql_data['email'] = $sql_data['email']['address'];
-        }
-        // avoid value being null
-        if (empty($sql_data['email'])) {
-            $sql_data['email'] = '';
+        foreach ($object as $colname => $value) {
+            list($col, $field) = explode(':', $colname);
+            if ($col == 'email' && !empty($value)) {
+                $sql_data['email'] = is_array($value) ? $value[0] : $value;
+                break;
+            }
         }
 
         // use organization if name is empty
@@ -78,21 +78,18 @@ class kolab_storage_cache_contact extends kolab_storage_cache
     public function get_words($object)
     {
         $data = '';
-        foreach ($this->fulltext_cols as $colname) {
+
+        foreach ($object as $colname => $value) {
             list($col, $field) = explode(':', $colname);
 
-            if ($field) {
-                $a = [];
-                foreach ((array)$object[$col] as $attr)
-                    $a[] = $attr[$field];
-                $val = join(' ', $a);
-            }
-            else {
-                $val = is_array($object[$col]) ? join(' ', $object[$col]) : $object[$col];
+            $val = '';
+            if (in_array($col, $this->fulltext_cols)) {
+                $val = is_array($value) ? join(' ', $value) : $value;
             }
 
-            if (strlen($val))
+            if (strlen($val)) {
                 $data .= $val . ' ';
+            }
         }
 
         return array_unique(rcube_utils::normalize_string($data, true));
diff --git a/plugins/libkolab/lib/kolab_storage_dav_folder.php b/plugins/libkolab/lib/kolab_storage_dav_folder.php
index 32ecdd5d..c7a46f47 100644
--- a/plugins/libkolab/lib/kolab_storage_dav_folder.php
+++ b/plugins/libkolab/lib/kolab_storage_dav_folder.php
@@ -32,12 +32,9 @@ class kolab_storage_dav_folder extends kolab_storage_folder
     public function __construct($dav, $attributes, $type_annotation = '')
     {
         $this->attributes = $attributes;
-        $this->href = $this->attributes['href'];
 
-        // Here we assume the last element of the folder path is the folder ID
-        // if that's not the case, we should consider generating an ID
-        $href        = explode('/', unslashify($this->href));
-        $this->id    = $href[count($href) - 1];
+        $this->href  = $this->attributes['href'];
+        $this->id    = md5($this->href);
         $this->dav   = $dav;
         $this->valid = true;
 
@@ -410,8 +407,9 @@ class kolab_storage_dav_folder extends kolab_storage_folder
 
         // generate and save object message
         if ($content = $this->to_dav($object)) {
-            $method = $uid ? 'update' : 'create';
-            $result = $this->dav->{$method}($this->object_location($object['uid']), $content);
+            $method   = $uid ? 'update' : 'create';
+            $dav_type = $this->get_dav_type();
+            $result   = $this->dav->{$method}($this->object_location($object['uid']), $content, $dav_type);
 
             // Note: $result can be NULL if the request was successful, but ETag wasn't returned
             if ($result !== false) {
@@ -473,10 +471,24 @@ class kolab_storage_dav_folder extends kolab_storage_folder
 
             $result = $events[0];
         }
+        else if ($this->type == 'contact') {
+            if (stripos($object['data'], 'BEGIN:VCARD') !== 0) {
+                return false;
+            }
+
+            $vcard = new rcube_vcard($object['data'], RCUBE_CHARSET, false);
+
+            if (!empty($vcard->displayname) || !empty($vcard->surname) || !empty($vcard->firstname) || !empty($vcard->email)) {
+                $result = $vcard->get_assoc();
+            }
+            else {
+                return false;
+            }
+        }
 
         $result['etag'] = $object['etag'];
         $result['href'] = $object['href'];
-        $result['uid'] = $object['uid'] ?: $result['uid'];
+        $result['uid']  = $object['uid'] ?: $result['uid'];
 
         return $result;
     }
@@ -496,6 +508,35 @@ class kolab_storage_dav_folder extends kolab_storage_folder
 
             $result = $ical->export([$object]);
         }
+        else if ($this->type == 'contact') {
+            // copy values into vcard object
+            $vcard = new rcube_vcard('', RCUBE_CHARSET, false, ['uid' => 'UID']);
+
+            $vcard->set('groups', null);
+
+            foreach ($object as $key => $values) {
+                list($field, $section) = rcube_utils::explode(':', $key);
+
+                // avoid casting DateTime objects to array
+                if (is_object($values) && is_a($values, 'DateTime')) {
+                    $values = [$values];
+                }
+
+                foreach ((array) $values as $value) {
+                    if (isset($value)) {
+                        $vcard->set($field, $value, $section);
+                    }
+                }
+            }
+
+            $result = $vcard->export(false);
+        }
+
+        if ($result) {
+            // The content must be UTF-8, otherwise if we try to fetch the object
+            // from server XML parsing would fail.
+            $result = rcube_charset::clean($result);
+        }
 
         return $result;
     }