After a break in regularly compiling git on my Mac 10.7.3 laptop, I had a few tests fail: t5540.15, t5541.{12,15}. All of these tests use test_i18ngrep to test the output of git-push for the string "To prevent you from losing history, non-fast-forward updates were rejected".
Bisecting traced it back to f25950f: "push: Provide situational hints for non-fast-forward errors".
I'm sending this off to the list in case someone else has some idea of the root cause. I'll get back to this problem myself sometime tomorrow.
~~ Brian Gernhardt