diff --git a/Kwf/Form/Field/SuperBoxSelect.php b/Kwf/Form/Field/SuperBoxSelect.php
index <HASH>..<HASH> 100644
--- a/Kwf/Form/Field/SuperBoxSelect.php
+++ b/Kwf/Form/Field/SuperBoxSelect.php
@@ -33,6 +33,7 @@ class Kwf_Form_Field_SuperBoxSelect extends Kwf_Form_Field_ComboBox
 
     private function _getIdsFromPostData($postData)
     {
+        if (!$postData[$this->getFieldName()]) return array();
         return explode(',', $postData[$this->getFieldName()]);
     }
fix saving of SuperBoxSelect without selected entries