Как отключить эту задержку, и с чем она может быть связана?
Другие сервисы внутри Jail как apache работают без всяких задержек.

Вот конфиг этого proftpd

#
# For more informations about Proftpd configuration
# look at : http://www.proftpd.org/
#
# This is a basic ProFTPD configuration file (rename it to
# 'proftpd.conf' for actual use.  It establishes a single server
# and a single anonymous login.  It assumes that you have a user/group
# "nobody" and "ftp" for normal operation and anon.

ServerName            "ProFTPD Default Installation"
ServerType            standalone
DefaultServer            on
ScoreboardFile        /var/run/proftpd/proftpd.scoreboard

# Port 21 is the standard FTP port.
Port                21

# Use IPv6 support by default.
#UseIPv6                off

# Umask 022 is a good standard umask to prevent new dirs and files
# from being group and world writable.
Umask                022

# To prevent DoS attacks, set the maximum number of child processes
# to 30.  If you need to allow more than 30 concurrent connections
# at once, simply increase this value.  Note that this ONLY works
# in standalone mode, in inetd mode you should use an inetd server
# that allows you to limit maximum number of processes per service
# (such as xinetd).
MaxInstances            30

CommandBufferSize    512

# Set the user and group under which the server will run.
User                nobody
Group                nogroup

# To cause every FTP user to be "jailed" (chrooted) into their home
# directory, uncomment this line.
#DefaultRoot ~

# Normally, we want files to be overwriteable.
AllowOverwrite        on

# Bar use of SITE CHMOD by default
#<Limit SITE_CHMOD>
#  DenyAll
#</Limit>

# A basic anonymous configuration, no upload directories.  If you do not
# want anonymous users, simply delete this entire <Anonymous> section.

#########################################################################
#                                                                       #
# Uncomment lines with only one # to allow basic anonymous access       #
#                                                                       #
#########################################################################

#<Anonymous ~ftp>
#   User                ftp
#   Group                ftp

  ### We want clients to be able to login with "anonymous" as well as "ftp"
  # UserAlias            anonymous ftp

  ### Limit the maximum number of anonymous logins
  # MaxClients            10

  ### We want 'welcome.msg' displayed at login, and '.message' displayed
  ### in each newly chdired directory.
  # DisplayLogin            welcome.msg
  # DisplayFirstChdir        .message

  ### Limit WRITE everywhere in the anonymous chroot
  # <Limit WRITE>
  #   DenyAll
  # </Limit>
#</Anonymous>

DefaultRoot ~
ListOptions "-la"
DefaultRoot ~
DefaultRoot ~
AllowStoreRestart on