there's probably a file as mentioned by satinet (might be called local instead of boot.local, the existence and name of this file varies from distro to distro)
I know with Gentoo and Debian, there's a tool to set up this script if it doesn't exist. first, create /etc/init.d/local, make it call your script, chmod it to 755, then
update-rc.d local defaults 99
Wirh Gentoo, that's a little different... but I doubt Suse uses the Gentoo-type tool.
This will load your local script (with priority 99, so it'll load toward the end of the boot process), and it'll overwrite the settings made by Suse.
Good luck, let us know if it works!