Disk Tools HFS disk

While you are waiting for the Mac OS 8.1 CD, you can get by with an "HFS enabled" Disk Tools disk. "It is intended for use with Mac OS 8.1 and Mac OS Extended file format - in the event that you need to perform any troubleshooting and you do not have access to the Mac OS 8.1 CD." It's mentioned on Apple's 8.1 Update page. Or you can download it directly from Apple's ftp site. (Thanks, Sverre Toevik.)