When connecting to PureFTPd 1.0.21 server, some folders are unaccessible. Here is the content of the Journal log :

NOOP
226-Options: -l 
226 3 matches total
220---------- Welcome to Pure-FTPd [TLS] ----------
220-You are user number 2 of 6 allowed.
220-Local time is now 13:38. Server port: 21.
220-This is a private system - No anonymous login
220-IPv6 connections are also welcome on this server.
220 You will be disconnected after 31 minutes of inactivity.
USER georges
331 User georges OK. Password required
PASS ********
230-Your bandwidth usage is restricted
230-User georges has group access to:  82      
230-This server supports FXP transfers
230-OK. Current directory is /
230 23 Kbytes used (0%) - authorized: 33554432 Kb
FEAT
211-Extensions supported:
 EPRT
 IDLE
 MDTM
 SIZE
 REST STREAM
 MLST type*;size*;sizd*;modify*;UNIX.mode*;UNIX.uid*;UNIX.gid*;unique*;
 MLSD
 ESTP
 PASV
 EPSV
 SPSV
 ESTA
 AUTH TLS
 PBSZ
 PROT
 UTF8
211 End.
OPTS UTF8 ON
200 OK, UTF-8 enabled
CWD /OUTILS/Bibliotheque d'images
250 OK. Current directory is /OUTILS/Bibliotheque d'images
STAT /OUTILS/Bibliotheque d'images
213-STAT
213 End.
PASV
227 Entering Passive Mode (134,59,31,7,77,94)
MLSD
150 Accepted data connection
type=dir;sizd=646;modify=20081105095828;UNIX.mode=01777;UNIX.uid=501;UNIX.gid=501;unique=e00001fg299822; Logos

It seems that it hangs on the MLSD command. "Logos" is one of the 3 subdirectories of /OUTILS/Bibliotheque d'images, so it seems that the FTP server is answering correctly (but the end of the answer is missing) and this FTP server works correctly with other FTP Clients (though not verified if they use MLSD or not)

After executing

defaults write ch.sudo.cyberduck ftp.sendMlsdListCommand false

it works again.

Cyberduck version 3.1.2 had no such bug.