Git log can not show history before rename

From: Frank Li <lznuaa@gmail.com>
Date: Jan 30, 2009, 11:23 UTC
Message-ID: <1976ea660901300323n384d3650s3bb5a575accb65d1@mail.gmail.com>

mkdir tt3 cd tt3 git init-db touch a.c git add a.c git commit -a -m "test1"

git mv a.c b.c git commit -a -m "rename"

modify b.c git commit -a -m "test2"

git log -C -M -- b.c
========================================
commit 8d55ed63d2048d41bde8c34dafc52c6a965d61ed
Author: Frank Li <lznuaa@gmail.com>
Date:   Fri Jan 30 19:20:10 2009 +0800
    test2
commit af0214f7d32cf97fda2743e7d906305e6de2e9a2
Author: Frank Li <lznuaa@gmail.com>
Date:   Fri Jan 30 19:19:15 2009 +0800
    rename
=========================================

I can't get history before rename.