Codeception/c3 — pull request #13 by rajras (2014-12-01 17:09:46+00:00)
Title: Uptate condition in c3.php

I think that you need to change the condition of the autoload.
If you are working with codecept.phar and you also have composer for other purposes (ie: SF2 framework), you are getting a error because the \codeception\configuration class is not loaded.

kind regards.