Patch 0.97-os.3 adds support for PXE capable networks cards and thus
allows TFTP downloading with all recent network cards, like e1000, e100,
Broadcom (bnx2, b44, tg3), 3com and others.

To apply the patch you might want to do something like the following:
 - go to some writable directory like /tmp
 $ wget ftp://alpha.gnu.org/gnu/grub/grub-0.97.tar.gz
 $ wget http://os.inf.tu-dresden.de/~adam/grub/0.97/grub-0.97-os.3.diff.gz
 $ tar xzf grub-0.97.tar.gz
 $ cd grub-0.97
 $ zcat ../grub-0.97-os.3.diff.gz | patch -p0

Compile Grub with --enable-diskless --enable-pxe.
Add --enable-pci-direct if you get "no BIOS32 detected".
 $ ./configure --enable-diskless --enable-pxe
 $ make
(gcc-3.3 works)

Then add stage2/pxegrub to your DHCP configuration as the
NBP (network bootstrap program).
 $ cp netboot/pxegrub /tftp

For ISC dhcpd add
  filename "/tftp/pxegrub";
in a e.g. host or group block.

The default location to load initially is '(nd)/tftp/menu.lst'. 
To change this either change the corresponding line in
stage2/asm.S and recompile or change the string in the pxegrub binary.
There's space left after the string in the binary so that the new path and
filename can be longer.

This directory also contains a pxegrub binary, for use without first
applying the patch and compiling. You can also change the initial path in
binary directly as described above.

Adam