RPC , string parameter is sent, but length is 0

Hey, this is called by the server

                 player.Add(new PlayerStruct{ name = playername, ID = currPlayerJoinedID, isHost = false});
                 BinaryFormatter bf = new BinaryFormatter();
                 MemoryStream o = new MemoryStream(); 
                 bf.Serialize(o, player); 
                 string data = Utils.StreamConverter.ConvertMemoryStreamToString(o);
                 print (data.Length);
                 networkView.RPC("renewPlayerData",RPCMode.Others,data);

And this is the RPC, called by clients

         [RPC]
         void renewPlayerData(string listData)
         {
             
             player.Clear();
             BinaryFormatter bf = new BinaryFormatter();
             MemoryStream ins = new MemoryStream(Encoding.Default.GetBytes(listData)); 
             player = (List<PlayerStruct>)bf.Deserialize(ins);    
         }

The parameter in the clientsection is length 0. But on Server its not 0. It seems that the paramter gets corrupted. Any solutions to that?