Automatically disabling PXE boot

Hello all.

I'm returning to FAI after being forced to use xCat (long & sad story... 
short version: I didn't like it).
One of the features of xCat (possibly the only one I liked...) is that I 
can avoid touching BIOS configuration on the client, leaving it to 
always try PXE first and fallback to HDD when PXE fails. That does have 
the advantage that I don't need IPMI or a tech near a crashed system: 
it's enough to have someone that can press the 'reset' button (or a 
cheap switched plug).

IIUC hooks are run on the system being installed, so I could use LAST 
hook to somehow signal FAI host to run "fai-chboot -d host". But that 
would leave DHCP server sending a DHCP OFFER for a PXE boot that's been 
disabled. Maybe I'm reinventing the wheel, but couldn't find anything.

Any hints?

TIA.

-- 
Diego Zuccato
DIFA - Dip. di Fisica e Astronomia
Servizi Informatici
Alma Mater Studiorum - Università di Bologna
V.le Berti-Pichat 6/2 - 40127 Bologna - Italy
tel.: +39 051 20 95786