Mmm, I decided to be un peu h4XX0Rz... 🙂 FTP at the command line seems to at least get as far as logging into this server. It uses an FTP server (Pure-FTPd) that is standards-compliant and should be compatible with Finder. But if I pop the IP address in Finder, I get the same results. My guess is that there's some weird oddity with the FTP server's settings that is confusing Finder.... 🙁 But I don't know what to do about it.