diff --git a/plugins/calendar/drivers/kolab/kolab_calendar.php b/plugins/calendar/drivers/kolab/kolab_calendar.php
index 59ebb609..d20cf822 100644
--- a/plugins/calendar/drivers/kolab/kolab_calendar.php
+++ b/plugins/calendar/drivers/kolab/kolab_calendar.php
@@ -66,10 +66,9 @@ class kolab_calendar
         $this->alarms = true;
       }
       else {
-        $acl = $this->storage->_folder->getACL();
-        if (is_array($acl)) {
-          $acl = $acl[$_SESSION['username']];
-          if (strpos($acl, 'i') !== false)
+        $rights = $this->storage->_folder->getMyRights();
+        if (!PEAR::isError($rights)) {
+          if (strpos($rights, 'i') !== false)
             $this->readonly = false;
         }
       }
diff --git a/plugins/kolab_addressbook/lib/rcube_kolab_contacts.php b/plugins/kolab_addressbook/lib/rcube_kolab_contacts.php
index 1a16d762..6bd473f2 100644
--- a/plugins/kolab_addressbook/lib/rcube_kolab_contacts.php
+++ b/plugins/kolab_addressbook/lib/rcube_kolab_contacts.php
@@ -127,12 +127,11 @@ class rcube_kolab_contacts extends rcube_addressbook
                 $this->readonly = false;
             }
             else {
-                $acl = $this->storagefolder->getACL();
-                if (!PEAR::isError($acl) && is_array($acl)) {
-                    $acl = $acl[$_SESSION['username']];
-                    if (strpos($acl, 'i') !== false)
+                $rights = $this->storagefolder->getMyRights();
+                if (!PEAR::isError($rights)) {
+                    if (strpos($rights, 'i') !== false)
                         $this->readonly = false;
-                    if (strpos($acl, 'a') !== false || strpos($acl, 'x') !== false)
+                    if (strpos($rights, 'a') !== false || strpos($rights, 'x') !== false)
                         $this->editable = true;
                 }
             }