When I got my new computer about a year ago, I transferred all my files via ethernet from my OS9 Mac to the new one. In the process, although I didn't know it at the time - all the file info comments disappeared. When I found I needed the comments on a set of files a few months later - they were gone. It turns out though, that I had backed up some of the files on CD before moving them over, and these retained the comments. However they are unreadable in OSX and I didn't feel like booting into OS9 since I've had disastrous results doing that on another computer.

There are several utilities available that let you read the comments. None of them are terribly polished, but one worked for me:
"Comment Synch" allows you to browse for files and see the OS9 comments. You can also set OSX comments.

Comment Synch is shareware and available here