[Ham-Mac] changing owners on osx

[Patricia Reiff]

Heres a very dumb question. I bought a used ibook, and I want to change 
the owner name and password when I upgrade to panther, but i don't want 
to wipe the disk because I want to keep the ability to boot in os 9.2.

What do I do?

thanks...
...Pat KD5IZK