Python as network protocol

[Cooch]

Hi, guys!

I want to implement such specific feature:
I have a server written in Python. I have a client written in C++. I
want to use Python as network protocol between them. I mean: client
send to server such string: "a = MyObject()", so object of this type
will appear in server. Any ideas how to simplify this implementation?
I make XML-RPC/SOAP server using twisted which just execute sended
string. But I don't know how to:
1. Restrict usage of some modules on client side (os, sys etc..)
2. Divide variables of different clients. Generally, I know that I
should use "exec .. in .. " construct, but don't know how to
distinguish between clients in twisted.

Dmitry.