I'm very happy for it!! I decided to post a short tutorial for help other people:
Setting up VGA out in your Ibook using Xorg
I saw many people trying unsuccessfuly to setup the VGA out feature of their ibooks (using a non-macos, of course). I intend to show here how to setup the VGA out using Xorg. I use Debian GNU/Linux, and I have super cow powers by using APT ;o) but this can be useful for other distributions too.
So, the first step is install Xorg. There is a good project called Debian-Desktop where are compiled and packaged some importants programs that still aren't on the oficial Debian mirrors. You can use a PPC version of Xorg provided by Debian-Desktop, adding this line in your /etc/apt/sources.list:
deb http://www.debian-desktop.org/pub/linux/debian/xorg-6.8.2/ sarge main
It also works well on Debian SID. Now you just run these commands:
aptitude install xserver-xorg
You can get my xorg.conf here and put it in your /etc/X11/ dir. It's working very well on my ibook G4 1Ghz.
Thanks to otavio, the man that really has found this solution for us.