diff --git a/plugins/calendar/calendar.php b/plugins/calendar/calendar.php
index d9bfb300..2fc10313 100644
--- a/plugins/calendar/calendar.php
+++ b/plugins/calendar/calendar.php
@@ -1245,11 +1245,14 @@ class calendar extends rcube_plugin
           $organizer = true;
         if ($attendee['email'] == $identity['email'])
           $owner = $i;
+        else if (!isset($attendee['rsvp']))
+          $event['attendees'][$i]['rsvp'] = true;
       }
       
       // set owner as organizer if yet missing
       if (!$organizer && $owner !== false) {
         $event['attendees'][$i]['role'] = 'ORGANIZER';
+        unset($event['attendees'][$i]['rsvp']);
       }
       else if (!$organizer && $identity['email'] && $action == 'new') {
         array_unshift($event['attendees'], array('role' => 'ORGANIZER', 'name' => $identity['name'], 'email' => $identity['email'], 'status' => 'ACCEPTED'));
diff --git a/plugins/calendar/drivers/calendar_driver.php b/plugins/calendar/drivers/calendar_driver.php
index d8d4230e..d5015a2d 100644
--- a/plugins/calendar/drivers/calendar_driver.php
+++ b/plugins/calendar/drivers/calendar_driver.php
@@ -64,6 +64,7 @@
  *           'email' => 'Participant e-mail address',  // used as identifier
  *            'role' => 'ORGANIZER|REQ-PARTICIPANT|OPT-PARTICIPANT|CHAIR',
  *          'status' => 'NEEDS-ACTION|UNKNOWN|ACCEPTED|TENTATIVE|DECLINED'
+ *            'rsvp' => true|false,
  *    ),
  *  );
  */
diff --git a/plugins/calendar/drivers/kolab/kolab_calendar.php b/plugins/calendar/drivers/kolab/kolab_calendar.php
index e3a4b255..c4620742 100644
--- a/plugins/calendar/drivers/kolab/kolab_calendar.php
+++ b/plugins/calendar/drivers/kolab/kolab_calendar.php
@@ -550,6 +550,7 @@ class kolab_calendar
         'name' => $attendee['display-name'],
         'email' => $attendee['smtp-address'],
         'status' => $status_map[$attendee['status']],
+        'rsvp' => $attendee['request-response'],
       );
       $_attendees .= $rec['organizer']['display-name'] . ' ' . $rec['organizer']['smtp-address'] . ' ';
     }
@@ -737,6 +738,7 @@ class kolab_calendar
           'smtp-address' => $attendee['email'],
           'status' => $this->status_map[$attendee['status']],
           'role' => $this->role_map[$role],
+          'request-response' => $attendee['rsvp'],
         );
       }
     }
diff --git a/plugins/calendar/lib/calendar_ical.php b/plugins/calendar/lib/calendar_ical.php
index 09427abb..a7ce7604 100644
--- a/plugins/calendar/lib/calendar_ical.php
+++ b/plugins/calendar/lib/calendar_ical.php
@@ -40,6 +40,9 @@ class calendar_ical
   private $rc;
   private $cal;
   private $timezone = 'Z';
+  
+  public $method;
+  public $events = array();
 
   function __construct($cal)
   {
@@ -70,15 +73,16 @@ class calendar_ical
     
     $parser = new Horde_iCalendar;
     $parser->parsevCalendar($vcal, 'VCALENDAR', $charset);
-    $events = array();
+    $this->method = $parser->getAttributeDefault('METHOD', '');
+    $this->events = array();
     if ($data = $parser->getComponents()) {
       foreach ($data as $comp) {
         if ($comp->getType() == 'vEvent')
-          $events[] = $this->_to_rcube_format($comp);
+          $this->events[] = $this->_to_rcube_format($comp);
       }
     }
     
-    return $events;
+    return $this->events;
   }
 
   /**
@@ -100,11 +104,11 @@ class calendar_ical
     // check for all-day dates
     if (is_array($event['start'])) {
       // create timestamp at 00:00 in user's timezone
-      $event['start'] = strtotime(sprintf('%04d%02d%02dT000000%s', $event['start']['year'], $event['start']['month'], $event['start']['mday'], $this->timezone));
+      $event['start'] = $this->_date2time($event['start']);
       $event['allday'] = true;
     }
     if (is_array($event['end'])) {
-      $event['end'] = strtotime(sprintf('%04d%02d%02dT000000%s', $event['end']['year'], $event['end']['month'], $event['end']['mday'], $this->timezone)) - 60;
+      $event['end'] = $this->_date2time($event['end']) - 60;
     }
 
     // map other attributes to internal fields
@@ -171,6 +175,10 @@ class calendar_ical
         
         case 'EXDATE':
           break;
+          
+        case 'RECURRENCE-ID':
+          $event['recurrence_id'] = $this->_date2time($attr['value']);
+          break;
         
         case 'DESCRIPTION':
         case 'LOCATION':
@@ -202,8 +210,26 @@ class calendar_ical
     
     return $event;
   }
+  
+  /**
+   * Helper method to correctly interpret an all-day date value
+   */
+  private function _date2time($prop)
+  {
+    // create timestamp at 00:00 in user's timezone
+    return is_array($prop) ? strtotime(sprintf('%04d%02d%02dT000000%s', $prop['year'], $prop['month'], $prop['mday'], $this->timezone)) : $prop;
+  }
 
 
+  /**
+   * Free resources by clearing member vars
+   */
+  public function reset()
+  {
+    $this->method = '';
+    $this->events = array();
+  }
+
   /**
    * Export events to iCalendar format
    *
@@ -329,6 +355,8 @@ class calendar_ical
       else {
         //I am an attendee 
         $attendees .= "ATTENDEE;ROLE=" . $at['role'] . ";PARTSTAT=" . $at['status'];
+        if ($at['rsvp'])
+          $attendees .= ";RSVP=TRUE";
         if (!empty($at['name']))
           $attendees .= ';CN="' . $at['name'] . '"';
         $attendees .= ":mailto:" . $at['email'] . self::EOL;