Knoppix 5.1: howto start beryl after HD-install?

Beryl runs perfectly from the live-CD and I installed Knoppix 5.1 with no problems (using ext3 not reiserfs!) in a dual boot with XP on my laptop. Booting from the HD provides me no grub boot prompt and so I get the normal KDE desktop after booting. In the /boot/grub/menu.lst I inserted the option 'desktop=beryl' in the line 'kernel /boot/vmlinuz root=/dev/sda4 rw ... vga=791 desktop=beryl' but this did not change anything after re-booting. What do I have to do to get automatically, or at least manually, composite, aiglx, and beryl running with the HD-install?
thanks a lot,
-p.

chnage your xorg.conf according to the instructions in http://en.opensuse.org/Beryl#Beryl_with_X.org_AIGLX and things work out fine!