How to enable 3d acceleration w/ Rage Mobility (mach64)

short howto for debian-based linux:
Download the drm-modules-source and build the modules:

tar xzvf drm-mach64.tar.gz
cd drm/linux-core
make mach64.o

... replace the kernel module drm.ko with compiled module drm.ko
... copy mach64.ko to the kernel modules directory
... and set max Display Depth to 16 bit (xorg.conf).

Here how-to for Ubuntu (and deb-packages)