[protobuf] Python with PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION=cpp

Hi all, I am having issues trying to make use of the C++ binding for Python. I am running Ubuntu 12.10, and trying to create a virtualenv to run some python applications that use protobufs. I wanted to try using the PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION=cpp variable to measure the

[protobuf] Ubuntu: Trouble with EXPERIMENTAL C++ Implmenetation

I'm trying to install a virtualenv for python apps that use protobufs. I would like to get the improved performance from the C++ bindings. However, when I try the following, I get errors indicating that a python_descriptor.cc isn't found. Any thoughts would be greatly appreciated !!