zendframework/zf2 — pull request #6301 by tklever (2014-05-20 18:57:11+00:00)
Title: Replacing self:: with static:: in Http\Client::setAuth

This becomes an issue if you want to create a custom authentication method in a class extending Http\Client

The self:: check only allows for the included constants (AUTH_BASIC and AUTH_DIGEST), and will throw an exception on AUTH_XXXX constants in extending classes.