Codeception/Codeception — pull request #148 by Incubatio (2013-02-09 00:41:08+00:00)
Title: Zend_Controller_Response_HttpTestCase

Use Zend_Controller_Response_HttpTestCase instead of Zend_Controller_Response_Http that is basically developped for tests.
It's also used in ControllerTestCase that was your reference when you "ported" source code for codeception according to your documentation.