proxyDHCP and pxe

I am trying to come up with a DHCP configuration that will allow a pxe client to boot just like the 3com pxe server with proxyDHCP setting.

basically the ip address needs to come from the authoritative DHCP (which the machine has a static DHCP assigned address) yet get the additional information for pxe booting)

i have researched and come up with this document from opensuse wiki with a code snipit:

[INDENT]default-lease-time 600;
max-lease-time 7200;
ddns-update-style none; ddns-updates off;
allow booting;

option domain-name “my.domain”;
option domain-name-servers my.dnsserver;
option routers my.router;

define rules to identify DHCP Requests from PXE and Etherboot clients.

class “pxe” {
match if substring (option vendor-class-identifier, 0, 9) = “PXEClient”;
class “etherboot” {
match if substring (option vendor-class-identifier, 0, 9) = “Etherboot”;

subnet netmask {
option broadcast-address;
pool {
default-lease-time 180; # no long lease time required for booting
max-lease-time 360; # booted system does its own dhcp request
server-name “mybootserver”;
next-server mybootserver.; # in case your local DNS only handles
# unqualified domains keep trailing ‘.’
filename “pxelinux.0”;
allow members of “pxe”;
allow members of “etherboot”; # allow etherboot, too

but it still has a subnet tag other than what is already there. is there a way to use dhcp-relay to do this in linux?

I think the answer is proxyDHCP and dnsmasq but what would the config file look like? how to add and subtract hosts from it?