Someone

#!/bin/sh
Xgl -fullscreen :1 -ac -br -accel glx:pbuffer -accel xv:pbuffer &
sleep 4  
export DISPLAY=:1 
cookie="$(xauth -i nextract - :0 | cut -d ' ' -f 9)"
xauth -i add :1 . "$cookie"
exec gnome-session

#!/bin/sh
Xgl :1 -fullscreen -ac -accel xv:pbuffer -accel glx:pbuffer &
DISPLAY=:1
exec dbus-launch --exit-with-session gnome-session