Index: game/Inventory/Inventory.cpp
===================================================================
--- game/Inventory/Inventory.cpp	(revision 5694)
+++ game/Inventory/Inventory.cpp	(working copy)
@@ -607,7 +607,8 @@ CInventoryItemPtr CInventory::PutItem(idEntity *ent, idEntity *owner)
 
 		// We added a stackable item that was already in the inventory
 		gameLocal.m_MissionData->InventoryCallback(
-			existing->GetItemEntity(), existing->GetName(), 
+			ent, // use currently added entity, not the previously added "identical" existing->GetItemEntity() (#3315)
+			existing->GetName(), 
 			existing->GetCount(), 
 			1, 
 			true