defunkt/jquery-pjax — pull request #211 by shaneriley (2012-10-11 18:20:55+00:00)
Title: Fire passed in ajax callbacks

The documentation on the $.pjax method currently states: "It acts much like $.ajax, even returning the same thing and accepting the same options.". If you pass an options object in with success, error, complete, or beforeSend callbacks, however, they are overwritten after the options object is extended, deleting the callbacks passed in.