In the current master (and 1.7.4), tab completion for refs doesn't work in zsh. When typing "git log orig<TAB>", nothing appears.
A revision that works for me is 5a3a484d57. I suspect it may have something to do with dbda3b1090, but it's hard to bisect because many revisions on the way can't even be loaded by zsh.
I don't know enough about the completion mechanisms to be able to debug this myself. Anybody able to help?
(My zsh version is 4.3.9, in case it makes a difference.)
-- Stefan Haller Berlin, Germany http://www.haller-berlin.de/