PXE booting HEAD

Hi,
I'm in the way to prepare a current boot from net, and I'll know if:

- I can safe compile (Well ...) HEAD in a RELENG_5_4 machine.

- There're info about the safe form to get this working.

I'll use:
- a RELENG_5_4 build machine / nfs server
- pxe boot the machine from dhcp/tftp
- use exports/ctest (dedicated) and /home.

Thanks in advance,
--
  josemi