http://syslinux.zytor.com/pxe.php#tftp
According to this, you need a special tftp server that ..
which supports the "tsize" TFTP option (RFC 1784/RFC 2349).
Does anyone know off the top of their head if the tftp server that
"comes with" Red Hat 9 will work for booting PXELINUX per the
requirements above.
Tommy