RESOLUTION
Try to stop/start xinetd:
/etc/init.d/xinetd restart
Also take a look at the /var/log/messages file for detailed error reports.The server hostname may not beĀ resolved. In this case you should put the record like "SERVER_IP SERVER_HOSTNAME" into /etc/hosts.
CheckĀ firewall settings to be sure that 20/21 ports are opened.