I tried moving some files from my linux server to the external firewire drive on my iMac. It just did not work and my iMac would not see the UTF-8 encoded filenames. Then I learned about the utf-8-mac encoding and though wtf. My gentoo linux installation doesn't know about that. (NT_STATUS_OBJECT_NAME_NOT_FOUND)
I tried muCommander and bash in the hope that Finder was just screwing up. But nope...
ls: 耳をすませば サウンドトラック « Whisper of the Heart/: No such file or directory
So, after fiddling around, I used MacFUSE and MacFusion user-interface to mount my homedirectory via ssh. That works.
I guess that's another -1 point for OS X.
Also, I could not overwrite files starting with a dot (normally invisible in Finder). It gives "Error code -43". Oh well, that's just a feature.