Everything is in that XF86Config-4, create one with dpkg-reconfigure and another with old xf86config . And run diff for both . You will get a diffrence.
You could try one more command as a root # XFree86 -configure --------------------------------------- abhisawa -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]