I am using rsync to sync from my ubuntu machine (ext3) to my mac (HFS+ disk image). When I use the --delete flag, i get the following problem: deleting bart/Fotos/André.jpg bart/Fotos/André.jpg Any file containing a special character (éäëüê etcetera) gets deleted and then resynced. When I omit the --delete flag, rsync does everything normally. I tested with 2.6.9 and 3.0.5 and both have the exact same behavior. The files themselves are completely correct (no corruption or anything), so my guess is the delete checking has problems comparing the two filenames across the different filesystems and then falsely marks them as deleted.
The FAQ discusses a problem copying to HFS+: http://rsync.samba.org/FAQ.html#2 Is this what you are seeing?
Man do I feel like an idiot. I searched all the bugzilla tickets extensively but never looked at the rsync faq. Sorry about this!