I found a problem in default configuration $ cd /usr/X11R6/share/X11/xorg.conf.d/
There is a fpit file (50-fpit.conf) , it is a "Fujitsu Stylistic input driver" for tablet PCs. I deleted 50-fpit.conf and now X works very well, with "radeon" driver. That file should be removed from macppc default installation. Thanks -- luca suriano
