diff --git a/plugins/kolab_activesync/kolab_activesync.js b/plugins/kolab_activesync/kolab_activesync.js
index 7146a804..3e1d826c 100644
--- a/plugins/kolab_activesync/kolab_activesync.js
+++ b/plugins/kolab_activesync/kolab_activesync.js
@@ -56,7 +56,7 @@ function kolab_activesync_config()
     });
 
     var fn = function(elem) {
-      var classname = elem.className,
+      var classname = elem.className.split(' ')[0],
         list = $(elem).closest('table').find('input.' + classname),
         check = list.not(':checked').length > 0;
 
diff --git a/plugins/kolab_delegation/kolab_delegation.js b/plugins/kolab_delegation/kolab_delegation.js
index f6e320b6..062a2579 100644
--- a/plugins/kolab_delegation/kolab_delegation.js
+++ b/plugins/kolab_delegation/kolab_delegation.js
@@ -93,7 +93,7 @@ window.rcmail && rcmail.addEventListener('init', function(evt) {
       });
 
       var fn = function(elem) {
-        var classname = elem.className,
+        var classname = elem.className.split(' ')[0],
           list = $(elem).closest('table').find('input.' + classname),
           check = list.not(':checked').length > 0;