NPE fix

L2_GameServer/java/com/l2jserver/gameserver/model/quest/QuestState.java

@@ -534,7 +534,7 @@ public final class QuestState
 		long count = 0;
 
 		for (L2ItemInstance item : getPlayer().getInventory().getItems())
-			if (item.getItemId() == itemId)
+			if (item != null && item.getItemId() == itemId)
 				count += item.getCount();
 
 		return count;