Index: trunk/kernel/units/visits/visits_event_handler.php
===================================================================
diff -u -N -r2434 -r2437
--- trunk/kernel/units/visits/visits_event_handler.php	(.../visits_event_handler.php)	(revision 2434)
+++ trunk/kernel/units/visits/visits_event_handler.php	(.../visits_event_handler.php)	(revision 2437)
@@ -83,7 +83,7 @@
 					$object->addCalculatedField('OrderAffiliateCommissionSum', 'SUM(ord.AffiliateCommission)');
 					$object->addCalculatedField('OrderCountByVisit', 'COUNT(OrderId)');
 			}
-			if (!$types){
+			if (method_exists($object, 'AddGroupByField') && !$types){
 					$object->AddGroupByField('%1$s.VisitId');
 			}
 			
Index: trunk/core/units/visits/visits_event_handler.php
===================================================================
diff -u -N -r2434 -r2437
--- trunk/core/units/visits/visits_event_handler.php	(.../visits_event_handler.php)	(revision 2434)
+++ trunk/core/units/visits/visits_event_handler.php	(.../visits_event_handler.php)	(revision 2437)
@@ -83,7 +83,7 @@
 					$object->addCalculatedField('OrderAffiliateCommissionSum', 'SUM(ord.AffiliateCommission)');
 					$object->addCalculatedField('OrderCountByVisit', 'COUNT(OrderId)');
 			}
-			if (!$types){
+			if (method_exists($object, 'AddGroupByField') && !$types){
 					$object->AddGroupByField('%1$s.VisitId');
 			}