Index: custom_data/custom_data_event_handler.php
===================================================================
--- custom_data/custom_data_event_handler.php	(revision 12650)
+++ custom_data/custom_data_event_handler.php	(working copy)
@@ -55,7 +55,7 @@
 				return false;
 			}
 
-			if (!$custom_fields || (defined('IS_INSTALL') && IS_INSTALL)) {
+			if (!$custom_fields || (defined('IS_INSTALL') && IS_INSTALL) || (defined('CUSTOM_FIELD_ADDED') && CUSTOM_FIELD_ADDED)) {
 				// query all custom fields at once -> saves 4 sqls queries
 				$sql = 'SELECT *
 						FROM '.TABLE_PREFIX.'CustomField';
Index: custom_fields/custom_fields_event_handler.php
===================================================================
--- custom_fields/custom_fields_event_handler.php	(revision 12650)
+++ custom_fields/custom_fields_event_handler.php	(working copy)
@@ -30,6 +30,7 @@
 
 			$section = $this->Application->getUnitOption($main_prefix.'.custom', 'PermSection');
 			$event->setEventParam('PermSection', $section);
+
 			return parent::CheckPermission($event);
 		}
 
@@ -188,6 +189,7 @@
 			/* @var $ml_helper kMultiLanguageHelper */
 
 			// call main item config to clone cdata table
+			define('CUSTOM_FIELD_ADDED', 1); // used in cdata::scanCustomFields method
 			$this->Application->getUnitOption($main_prefix, 'TableName');
 			$ml_helper->createFields($main_prefix.'-cdata');
 		}