Strange traffic in java sockets

I'am investigating strange problem. I'am using java Sockets for IPC. And i'am worrying about strange traffic. When i use c# and transfer strings via StreamWriter it is ok:

But when i use java and ObjectOutputStream\ObjectInputStream it is very strange:

First column is inbound traffic and second is outbound.

It is simple code:

ObjectOutputStream oos = ObjectOutputStream(clientScoket.getOutputStream())
oos.writeObject(someCustomObject);

on another side:

ObjectInputStream ois = ObjectInputStr开发者_如何学编程eam(clientSocket.getInputStream());
SomeCustomObject sco = oos.readObject();

How inbound traffic can be unequal to outbound? Anyone?

It's some sort of problem in sniffing loopback traffic under Windows. I tried and no tools found anything (Wireshark and WinPCap cannot loopback). When you use simple streams and just write some bytes it is okay. The problem appears only with ObjectIputStream.