Diskless booting -- how?

[dman]

I built grub 0.90 with diskless support and the proper NIC driver(s)
(I have several machines with different NICs I want to boot as
diskless).  I can boot grub (from a floppy or hard disk) and the
'bootp' command works.  The problem is that I don't know what to do
next to get the kernel and start booting it.  I have created a custom
kernel image that allows root-over-NFS and includes the NIC driver.

TIA,
-D

PS.  I'm not on the list so please cc me as the Mail-followup-to:
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