acpi + toshiba satellite p300d-20b

to install opensuse 11.1 i have had to choose kernel safe options.
this configures the boot with acpi=off.
with acpi=off i cant shutdown with power off, have to press the power
button.
also no cpu frequency scaling.

i have read elsewhere that i can use acpi_osi="Linux".
at least shutdown with power off  and cpu frequency scaling seem to work
when i use this boot parameter.

on this list i have read that vendors should not use this.

http://lists.opensuse.org/opensuse-mobile/2008-09/msg00003.html

are there any alternatives to get acpi working?
fixing, changing the dsdt?

regards
reinhard