Git: "No you can't handle my root!" (?)

Git is good, Git is great! All praise the Git! :-D

What do you people think about this strange phenomena?

localhost / # git --version
git version 1.6.4.4

localhost / # git init
Initialized empty Git repository in //.git/

localhost / # cd etc
localhost etc # git add X11/xorg.conf
fatal: pathspec 'etc/X11/xorg.conf' did not match any files

Aside from the obvious question of why would I want to Git the whole
tree ("But all files deserve the Holy Presence of the Git!"), why does
Git refuse the love offering from "/etc/X11/xorg.conf"? Is it because
it contains font directory configurations?

Commit and [ENTER] to all,

S! :-)