Index: C:/Documents and Settings/Anderson/workspace/L2_GameServer_c4/java/net/sf/l2j/gameserver/model/TradeList.java
===================================================================
--- C:/Documents and Settings/Anderson/workspace/L2_GameServer_c4/java/net/sf/l2j/gameserver/model/TradeList.java	(revision 1605)
+++ C:/Documents and Settings/Anderson/workspace/L2_GameServer_c4/java/net/sf/l2j/gameserver/model/TradeList.java	(working copy)
@@ -210,20 +210,22 @@
 			_log.warning(_owner.getName() + ": Attempt to modify locked TradeList!");
 			return null;
 		}
-
 		L2Object item = L2World.getInstance().findObject(objectId);
 		if(item == null || !(item instanceof L2ItemInstance))
 		{
 			_log.warning(_owner.getName() + ": Attempt to add invalid item to TradeList!");
 			return null;
 		}
-		
 		if(!((L2ItemInstance)item).isStackable() && count > 1)
 		{
 			_log.warning(_owner.getName() + ": Attempt to add non-stackable item to TradeList with count > 1!");
 			return null;
 		}
-
+		for (TradeItem checkitem : _items)
+		{
+			if (checkitem.getObjectId() == objectId)		
+				return null;
+		}
 		TradeItem titem = new TradeItem((L2ItemInstance)item, count, price);
 		_items.add(titem);