OS X Server :: Netboot Setting Menu Gone?

This problem is on a Xserv G4.

The problem happened on the server installed with x.3.9 runnig for over a year, giving AFP, FTP, NFS, services and runnig OPEN DIRECTORY in REPLICA. The DHCP service is provided by a Xserv g5 giving Netboot service on the same subnet.

In Server Admin, Netboot lost the setting menu as I was accessing it. So no ports to see, no images can be added. The only menus available are

Overview

Log

Clients

The start button is shadded, so not avaiable.

Through TERMINAL, with sudo serveradmin start netboot I get

serveradmin[1076} Exeption in docommand: *** -[NSCFArray addObject:}: attempt to insert nil netboot:error = "NIL_RESPONSE_ERR (*** -[NSCFArray addObject:}: attempt to insert nil)"

I have undated to TIGER X.4.3, but of couse, it is the same. Everything else works.

After reinstalling a NEW system a reconfiguring EVERYTHING, I again lost the menus of NetBoot as I accessed them !!

Booting witn and external FireWire drive with a clone of my working SYSTEM in x.3.9 has the menus but the ports can't be seen.

A hardware problem ?