There's a way!
Insert any OS 10.x disk (preferably 10.1) into your computer, restart
Hold down C to boot to the CD
When the Installer pops up, go into the menu next to the apple logo (Installer menu), and choose Reset Password...
From there, pick System Administrator (root), and change it's password to what you want (you don't need to know the old password, etc)
Then once that's done, click DOne, or QUIT, depending on the version of the installer, and go into the installer menu, select quit, and reboot
Do NOT hold down the C key this time
Once you are back in X, choose system prefs, and Login, here click the Login Window tab. Just choose the text boxes where Name and Password are, and fill name with: root
PassworD: Whatever you made it.
Remember to click the save button.
Now, choose the "Show Other User in list for network users" that way you can log in as root at the main screen. Exit system prefs (save if it asks), and log out.
At the login screen, choose Other user, and log in as root, you will now automatically always log in that way.
I hope it works