Help configure Xorg

[Lorenzo La Spada]

Hi all,

I just left Xfree86 to use Xorg on my ibook g4 (ppc), mainly for kde.
I missed how to configure xorg. Double clic on the Xdarwin.app icon  
(the one created by xorg) will launch Xorg but typing "startx" on the  
terminal will launch the xfree86 version of Xdarwin. How can I get  
rid of that?

I notice that I have no xorg.conf file in my /etc/x11 folder. I tryed  
to run "Xorg -configure" but it doesn't work.
Well, to resume I have both xorg and xfree86 version of xdarwin  
installed, but I don't understand, when kde is launched, which config  
file are used and how to set up Xorg to launch with the startx  
command (instead of xfree86).

Can someone help me to configure all that?

Thank you in advance for help.