t7400 broken on pu (Mac OS X)

The current pu fails on Mac OS, case insensitive FS.

Bisecting points out
commit 3f28e4fafc046284657945798d71c57608bee479
[snip]
Date:   Sun Jan 6 13:21:07 2013 +0700

    Convert add_files_to_cache to take struct pathspec

And I veryfied that the preceeding commit 05647d2d8a5dc456d1f4ef73 is OK.

It fails here: not ok 38 - gracefully add submodule with a trailing slash

A run of a modified t7400 looks like this: Is there anything more, that I can do to debug this?

[snip] ok 37 - do not add files from a submodule

expecting success: 

	git reset --hard &&
	echo 1 >&2 &&
	git commit -m "commit subproject" init &&
	echo 2 >&2 &&
	(cd init &&
	echo 3 >&2 &&
	 echo b > a) &&
	echo 4 >&2 &&
	git add init/ &&
	echo 5 >&2 &&
	git diff --exit-code --cached init &&
	echo 6 >&2 &&
	commit=$(cd init &&
	echo 7 >&2 &&
	 git commit -m update a >/dev/null &&
	echo 8 >&2 &&
	 git rev-parse HEAD) &&
	echo 9 >&2 &&
	git add init/ &&
	echo 10 >&2 &&
	test_must_fail git diff --exit-code --cached init &&
	echo 11 >&2 &&
	test $commit = $(git ls-files --stage |
		sed -n "s/^160000 \([^ ]*\).*/\1/p")

HEAD is now at 57f2622 super commit 1
1
[second 1b8c63f] commit subproject
 Author: A U Thor <author@example.com>
 1 file changed, 1 insertion(+), 1 deletion(-)
2
3
4
5
6
7
8
9
10
test_must_fail: command succeeded: git diff --exit-code --cached init
not ok 38 - gracefully add submodule with a trailing slash