rails/rails — pull request #4596 by kennyj (2012-01-22 02:46:34+00:00)
Title: Fix GH #4344. A defined callback in extended module should be called too.

It seems that this issue is introduced 66a587cf5590d37483d8aba64da5022df08ecf07.
Callbacks is compiled at different timing and context.

In 3.2.0.rc1
callbacks often is compiled in __define_runner method.

In 3.2.0.rc2
callbacks always is compiled in __run_callback method.