Hi,
You can't but you can change it. Unless the bootloader has password protection you just pass '1' or 'single' as an argument to the kernel at boot time and it will magically stop at runlevel one with you already root.
boot: linux single
From the # prompt you can then change the root password with :
# passwd (will prompt for new password)
On suse, I think its 'linux S' by the way.
Then you can reboot :
# /sbin/shutdown -r now
or
# init 6
This may seem a big weakness but the moral is protect your bootloader with a password and restrict physical access to the real console.
Hope this helps