I've forgotten the root password

[sunho baek]

Hi! Im Sunho.

I've forgotten the root password
So. I had searched for how to reset a root password.

The below is the result of my googling..

Single User Mode Booting..

OK> boot -s

........... <- message for searching the devices..

Selete the shell..

# fsck -p
# mount -a
# passwd root

But, I can't access the shell prompt.

My machine is installed FreeBSD 5.4.
What will I do?