Formatting a Win2k Drive?

I learned in a class over a year ago that in order to format & reload Win98 onto a hard drive that has Win2K on it, a simple format c: /s wouldn’t work. We had to run a program called “wipeout” (I think…) in order to make the drive fully reusablefor Win98. Does anyone know where I can find this program or an alternate solution for going back to Win98 on the same hard drive?