customize xorg.conf on an Xlivecd

hi all,

I am using catalyst-2.0-rc40 on an x86 with a 2006.0 stage3 as a seed stage.
I am doing a livecd booting directly on xorg-x11 so I have successfully achieved:
# catalyst2 -f livecd-stage1_template.spec
# catalyst2 -f livecd-stage2_template.spec
Here is the content of fsscript.sh:
echo "/etc/init.d/mkxf86config start"       >> /etc/conf.d/local.start
echo "/etc/init.d/x-setup start"                 >> /etc/conf.d/local.start
echo "startx"                                           >> /etc/conf.d/local.start
However, xorg breaks at startup and I found that the "speedo" module was the cause so I deleted it from 
xorg.conf
 and "startx" works.

I was wondering if it is possible to pass some parameters to the xorg.conf file for when 
"/etc/init.d/mkxf86config start" is called in a different way than customizing the "/usr/sbin/mkxf86config.sh" file by hand?

In my case I do not want that "speedo" module to be loaded (X breaks). Right now I am trying to adapt the "/usr/sbin/mkxf86config.sh" script to rebuild xorg.conf _without_ the "speedo" module and it is painful..so I am looking for an other way.

If any ideas pop up I would be glade to hear it,

Thanks by advance

Erick