It seems, the current /etc/ntp.conf is very complicated and non-working.
The xntpd server should work after installation immediately.
The working /etc/ntp.conf is here:

=================
# /etc/ntp.conf
#
# DENY all by default
#
restrict 0.0.0.0 mask 0.0.0.0 nopeer nomodify notrust

# Local Clock pseudo-driver stratum 3
#
server 127.127.1.0

# PERMIT ntp servers stratum 2 from http://www.ntp.org/
#To check : xntpdc
# >peer
# >reslist
#
server 130.235.20.3 prefer
restrict 130.235.20.3

server 129.132.98.11
restrict 129.132.98.11

server 130.228.230.2
restrict 130.228.230.2

server 194.192.207.9
restrict 194.192.207.9

# Drift for local clock
#
driftfile /etc/ntp/drift

# Don't use authentication
#
authenticate no