diff --git a/plugins/calendar/config.inc.php.dist b/plugins/calendar/config.inc.php.dist
--- a/plugins/calendar/config.inc.php.dist
+++ b/plugins/calendar/config.inc.php.dist
@@ -28,6 +28,9 @@
 // backend type (database, kolab, caldav)
 $config['calendar_driver'] = "database";
 
+// CalDAV server location (required when calendar_driver = caldav)
+$config['calendar_caldav_server'] = "http://localhost";
+
 // default calendar view (agendaDay, agendaWeek, month)
 $config['calendar_default_view'] = "agendaWeek";
 
diff --git a/plugins/calendar/skins/elastic/templates/calendar.html b/plugins/calendar/skins/elastic/templates/calendar.html
--- a/plugins/calendar/skins/elastic/templates/calendar.html
+++ b/plugins/calendar/skins/elastic/templates/calendar.html
@@ -8,9 +8,11 @@
 	<div class="header">
 		<a class="button icon back-content-button" href="#back" data-hidden="big"><span class="inner"><roundcube:label name="back" /></span></a>
 		<span id="aria-label-calendars" class="header-title"><roundcube:label name="calendar.calendars" /></span>
+		<roundcube:if condition="env:calendar_driver != 'caldav'" />
 		<roundcube:button name="calendaractionsmenu" id="calendaroptionsmenulink" type="link"
 			title="calendar.calendaractions" class="button icon sidebar-menu" data-popup="calendaractions-menu"
 			innerClass="inner" label="actions" />
+		<roundcube:endif />
 	</div>
 	<roundcube:object name="libkolab.folder_search_form" id="calendarlistsearch" wrapper="searchbar menu"
 		ariatag="h2" label="calsearchform" label-domain="calendar" buttontitle="findcalendars" />
@@ -141,11 +143,9 @@
 <div id="calendaractions-menu" class="popupmenu">
 	<h3 id="aria-label-calendaroptions" class="voice"><roundcube:label name="calendar.calendaractions" /></h3>
 	<ul class="menu listing" role="menu" aria-labelledby="aria-label-calendaroptions">
-		<roundcube:if condition="env:calendar_driver != 'caldav'" />
 		<roundcube:button type="link-menuitem" command="calendar-create" label="calendar.addcalendar" class="create disabled" classAct="create active" />
 		<roundcube:button type="link-menuitem" command="calendar-edit" label="calendar.editcalendar" class="edit disabled" classAct="edit active" />
 		<roundcube:button type="link-menuitem" command="calendar-delete" label="calendar.deletecalendar" class="delete disabled" classAct="delete active" />
-		<roundcube:endif />
 		<roundcube:if condition="env:calendar_driver == 'kolab'" />
 			<roundcube:button type="link-menuitem" command="calendar-remove" label="calendar.removelist" class="remove disabled" classAct="remove active" />
 		<roundcube:endif />
diff --git a/plugins/libcalendaring/libvcalendar.php b/plugins/libcalendaring/libvcalendar.php
--- a/plugins/libcalendaring/libvcalendar.php
+++ b/plugins/libcalendaring/libvcalendar.php
@@ -1353,6 +1353,9 @@
                 if (!empty($ex['thisandfuture'])) {
                     $recurrence_id->add('RANGE', 'THISANDFUTURE');
                 }
+
+                $ex['uid'] = $ve->UID;
+
                 $this->_to_ical($ex, $vcal, $get_attachment, $recurrence_id);
             }
         }
diff --git a/plugins/libkolab/SQL/mysql.initial.sql b/plugins/libkolab/SQL/mysql.initial.sql
--- a/plugins/libkolab/SQL/mysql.initial.sql
+++ b/plugins/libkolab/SQL/mysql.initial.sql
@@ -1,10 +1,3 @@
-/**
- * libkolab database schema
- *
- * @author Thomas Bruederli
- * @licence GNU AGPL
- */
-
 SET FOREIGN_KEY_CHECKS=0;
 
 DROP TABLE IF EXISTS `kolab_folders`;
diff --git a/plugins/libkolab/SQL/oracle.initial.sql b/plugins/libkolab/SQL/oracle.initial.sql
--- a/plugins/libkolab/SQL/oracle.initial.sql
+++ b/plugins/libkolab/SQL/oracle.initial.sql
@@ -1,10 +1,3 @@
-/**
- * libkolab database schema
- *
- * @author Aleksander Machniak
- * @licence GNU AGPL
- */
-
 CREATE TABLE "kolab_folders" (
     "folder_id" number NOT NULL PRIMARY KEY,
     "resource" VARCHAR(255) NOT NULL,
diff --git a/plugins/libkolab/SQL/sqlite.initial.sql b/plugins/libkolab/SQL/sqlite.initial.sql
--- a/plugins/libkolab/SQL/sqlite.initial.sql
+++ b/plugins/libkolab/SQL/sqlite.initial.sql
@@ -1,10 +1,3 @@
-/**
- * libkolab database schema
- *
- * @author Thomas Bruederli
- * @licence GNU AGPL
- */
-
 CREATE TABLE kolab_folders (
   folder_id INTEGER NOT NULL PRIMARY KEY,
   resource VARCHAR(255) NOT NULL,
diff --git a/plugins/libkolab/lib/kolab_dav_client.php b/plugins/libkolab/lib/kolab_dav_client.php
--- a/plugins/libkolab/lib/kolab_dav_client.php
+++ b/plugins/libkolab/lib/kolab_dav_client.php
@@ -25,6 +25,8 @@
 {
     public $url;
 
+    protected $user;
+    protected $password;
     protected $rc;
     protected $responseHeaders = [];
 
@@ -33,8 +35,22 @@
      */
     public function __construct($url)
     {
-        $this->url = $url;
         $this->rc = rcube::get_instance();
+
+        $parsedUrl = parse_url($url);
+
+        if (!empty($parsedUrl['user']) && !empty($parsedUrl['pass'])) {
+            $this->user     = rawurldecode($parsedUrl['user']);
+            $this->password = rawurldecode($parsedUrl['pass']);
+
+            $url = str_replace(rawurlencode($this->user) . ':' . rawurlencode($this->password) . '@', '', $url);
+        }
+        else {
+            $this->user     = $this->rc->user->get_username();
+            $this->password = $this->rc->decrypt($_SESSION['password']);
+        }
+
+        $this->url = $url;
     }
 
     /**
@@ -60,7 +76,7 @@
 
             $request = $this->initRequest($this->url . $path, $method, $request_config);
 
-            $request->setAuth($this->rc->user->get_username(), $this->rc->decrypt($_SESSION['password']));
+            $request->setAuth($this->user, $this->password);
 
             if ($body) {
                 $request->setBody($body);
@@ -144,7 +160,7 @@
             'VCARD' => 'addressbooks',
         ];
 
-        $principal_href = '/' . $roots[$component] . '/' . $this->rc->user->get_username();
+        $principal_href = '/' . $roots[$component] . '/' . rawurlencode($this->user);
 
         $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/">'
@@ -470,8 +486,10 @@
             $http_config = array_merge($http_config, $config);
         }
 
-        // load HTTP_Request2
-        require_once 'HTTP/Request2.php';
+        // load HTTP_Request2 (support both composer-installed and system-installed package)
+        if (!class_exists('HTTP_Request2')) {
+            require_once 'HTTP/Request2.php';
+        }
 
         try {
             $request = new HTTP_Request2();
diff --git a/plugins/libkolab/lib/kolab_storage_dav.php b/plugins/libkolab/lib/kolab_storage_dav.php
--- a/plugins/libkolab/lib/kolab_storage_dav.php
+++ b/plugins/libkolab/lib/kolab_storage_dav.php
@@ -227,7 +227,7 @@
      *
      * @return string Name of the folder-object
      */
-    public function object_name($folder, &$folder_ns = null)
+    public static function object_name($folder, &$folder_ns = null)
     {
         // TODO: Shared folders
         $folder_ns = 'personal';
diff --git a/plugins/libkolab/lib/kolab_storage_dav_cache.php b/plugins/libkolab/lib/kolab_storage_dav_cache.php
--- a/plugins/libkolab/lib/kolab_storage_dav_cache.php
+++ b/plugins/libkolab/lib/kolab_storage_dav_cache.php
@@ -138,7 +138,7 @@
         // Determine objects to fetch or delete
         $new_index    = [];
         $update_index = [];
-        $old_index    = $this->current_index(); // uid -> etag
+        $old_index    = $this->folder_index(); // uid -> etag
         $chunk_size   = 20; // max numer of objects per DAV request
 
         foreach ($dav_index as $object) {
@@ -162,7 +162,7 @@
         // Fetch new objects and store in DB
         if (!empty($new_index)) {
             foreach (array_chunk($new_index, $chunk_size, true) as $chunk) {
-                $objects = $this->folder->dav->getData($this->folder->href, $chunk);
+                $objects = $this->folder->dav->getData($this->folder->href, $this->folder->get_dav_type(), $chunk);
 
                 if (!is_array($objects)) {
                     rcube::raise_error([
@@ -190,7 +190,7 @@
         // Fetch updated objects and store in DB
         if (!empty($update_index)) {
             foreach (array_chunk($update_index, $chunk_size, true) as $chunk) {
-                $objects = $this->folder->dav->getData($this->folder->href, $chunk);
+                $objects = $this->folder->dav->getData($this->folder->href, $this->folder->get_dav_type(), $chunk);
 
                 if (!is_array($objects)) {
                     rcube::raise_error([
@@ -229,7 +229,7 @@
     /**
      * Return current folder index (uid -> etag)
      */
-    protected function current_index()
+    protected function folder_index()
     {
         // read cache index
         $sql_result = $this->db->query(
@@ -251,8 +251,9 @@
      *
      * @param string Object UID
      * @param string Object type to read
+     * @param string Unused (kept for compat. with the parent class)
      */
-    public function get($uid, $type = null)
+    public function get($uid, $type = null, $unused = null)
     {
         if ($this->ready) {
             $this->_read_folder_data();
@@ -283,8 +284,9 @@
      *
      * @param string      Object UID
      * @param array|false Hash array with object properties to save or false to delete the cache entry
+     * @param string      Unused (kept for compat. with the parent class)
      */
-    public function set($uid, $object)
+    public function set($uid, $object, $unused = null)
     {
         // remove old entry
         if ($this->ready) {
@@ -307,8 +309,9 @@
      *
      * @param mixed  Hash array with object properties to save or false to delete the cache entry
      * @param string Optional old message UID (for update)
+     * @param string Unused (kept for compat. with the parent class)
      */
-    public function save($object, $olduid = null)
+    public function save($object, $olduid = null, $unused = null)
     {
         // write to cache
         if ($this->ready) {
@@ -359,8 +362,10 @@
      *
      * @param string               Entry's  UID
      * @param kolab_storage_folder Target storage folder instance
+     * @param string Unused (kept for compat. with the parent class)
+     * @param string Unused (kept for compat. with the parent class)
      */
-    public function move($uid, $target)
+    public function move($uid, $target, $unused1 = null, $unused2 = null)
     {
         // TODO
     }
diff --git a/plugins/libkolab/lib/kolab_storage_dav_folder.php b/plugins/libkolab/lib/kolab_storage_dav_folder.php
--- a/plugins/libkolab/lib/kolab_storage_dav_folder.php
+++ b/plugins/libkolab/lib/kolab_storage_dav_folder.php
@@ -42,8 +42,8 @@
         $this->valid = true;
 
         list($this->type, $suffix) = explode('.', $type_annotation);
-        $this->default      = $suffix == 'default';
-        $this->subtype      = $this->default ? '' : $suffix;
+        $this->default = $suffix == 'default';
+        $this->subtype = $this->default ? '' : $suffix;
 
         // Init cache
         $this->cache = kolab_storage_dav_cache::factory($this);
@@ -140,6 +140,11 @@
         $host = preg_replace('|^https?://|', 'dav://' . urlencode($this->get_owner(true)) . '@', $this->dav->url);
         $path = $this->href[0] == '/' ? $this->href : "/{$this->href}";
 
+        $host_path = parse_url($host, PHP_URL_PATH);
+        if ($host_path && strpos($path, $host_path) === 0) {
+            $path = substr($path, strlen($host_path));
+        }
+
         $this->resource_uri = unslashify($host) . $path;
 
         return $this->resource_uri;
@@ -425,16 +430,17 @@
      *
      * @param string The object UID to fetch
      * @param string The object type expected (use wildcard '*' to accept all types)
+     * @param string Unused (kept for compat. with the parent class)
      *
      * @return mixed Hash array representing the Kolab object, a kolab_format instance or false if not found
      */
-    public function read_object($uid, $type = null)
+    public function read_object($uid, $type = null, $folder = null)
     {
         if (!$this->valid) {
             return false;
         }
 
-        $href = $this->object_location($uid);
+        $href    = $this->object_location($uid);
         $objects = $this->dav->getData($this->href, $this->get_dav_type(), [$href]);
 
         if (!is_array($objects) || count($objects) != 1) {
@@ -484,7 +490,6 @@
 
         if ($this->type == 'event') {
             $ical = libcalendaring::get_ical();
-
             if (!empty($object['exceptions'])) {
                 $object['recurrence']['EXCEPTIONS'] = $object['exceptions'];
             }
diff --git a/plugins/libkolab/libkolab.php b/plugins/libkolab/libkolab.php
--- a/plugins/libkolab/libkolab.php
+++ b/plugins/libkolab/libkolab.php
@@ -235,8 +235,10 @@
         $key = md5(serialize($http_config));
 
         if (!($request = self::$http_requests[$key])) {
-            // load HTTP_Request2
-            require_once 'HTTP/Request2.php';
+            // load HTTP_Request2 (support both composer-installed and system-installed package)
+            if (!class_exists('HTTP_Request2')) {
+                require_once 'HTTP/Request2.php';
+            }
 
             try {
                 $request = new HTTP_Request2();