[BUG] git ls-files -m --with-tree does double output

I think that this is wrong? The combination of -m and --with-tree shows duplicate entries. Git 1.6.0.2.

Cheers, Anders.

and@dylle:~$ mkdir repo ; cd repo
and@dylle:~/repo$ git init
Initialized empty Git repository in /home/and/repo/.git/
and@dylle:~/repo$ date >a ; git add a ; git commit -m'Add 1'
Created initial commit c027435: Add 1
 1 files changed, 1 insertions(+), 0 deletions(-)
 create mode 100644 a
and@dylle:~/repo$ date >a
and@dylle:~/repo$ git ls-files -m --with-tree=HEAD
a
a