How do I get a W2100z (Sun dual opteron box) to PXE boot?

I know how this is supposed to work. Hit F12 early on and it goes to
network boot. But it simply ignores it.

Going into the boot menu (and setup) doesn't show any network boot
options or PXE options at all. They're not disabled or anything like
that. They simply aren't present at all. Most odd.

--
-Peter Tribble
MRC Rosalind Franklin Centre for Genomics Research
http://www.rfcgr.mrc.ac.uk/~ptribble/ - http://ptribble.blogspot.com/