aticonfig and xorg.conf

[Gerard Robin <g.robin3@free.fr>]

Hello,
my box: acer aspire 51O2wlmi (amd64)
dist: Debian unstable (gnome metacity)

aticonfig --initial :
Uninitialised file found, configuring.
Using /etc/X11/xorg.conf
Saved back-up to /etc/X11/xorg.conf.original-1
*** glibc detected *** aticonfig: munmap_chunk(): invalid pointer: 0x00007fff29170f8a ***
........

I know that there is a problem with the driver ATI and linux, but atconfig --initial 
remove  /etc/X11/xorg.conf (and save it in /etc/X11/xorg.conf.original-1)
and, witout /etc/X11/xorg.conf, startx launches xwindow like charm. 

What have I missing ?

--
Gérard