diff --git a/app/code/community/OpenTools/Ordernumber/Model/Observer.php b/app/code/community/OpenTools/Ordernumber/Model/Observer.php
index 3102fd5b82edc73e91769d076dce2c2038e963cb..b30b3127a64ef8e5e637887bd8785ce90f97605c 100644
--- a/app/code/community/OpenTools/Ordernumber/Model/Observer.php
+++ b/app/code/community/OpenTools/Ordernumber/Model/Observer.php
@@ -114,7 +114,7 @@ class OpenTools_Ordernumber_Model_Observer extends Mage_Core_Model_Abstract
                     break;
                 default:
                     /* Pre-defined counter formats saved in the /reset config field */
-                    $counterfmt = $format . '|' . $reset;
+                    $format = $format . '|' . $reset;
                     break;
             }
             $customvars = Mage::getStoreConfig('ordernumber/replacements', $storeId);