I have set up my MyBook World I 1tb (firmware 2.00.18) as a SMB share to do complete backups with Retrospect Mac. It works great, never had any problems except one: illegal file names. As all of you know, I'm sure, and I have discovered, there are lots of characters allowed in Mac file names that aren't on the MyBook. Most cannot be changed (some are system files). I am a Mac, not Linux, geek, but I have a friend who can do a lot of the tough stuff, as long as I can tell him what to do. I'm not using it as a Time Machine drive, but I bet the steps are pretty similar.
1) I can't tell if the problem is SMB, Linux, or the format (UFS?) of the drive.
2) Do I need to switch from SMB to another network protocol like NFS or even FTP?
3) Is it possible/necessary to change the format of the drive to HFS+?