DCHPD working for PXE but not sending OFFER for ipconfig

I have an isolated subnet I am setting up for a compute cluster. They
are diskless Debian Squeeze nodes and I am configuring an isc dhcp
server. So far the only machines on the network are the dhcpd/tftpd/
nfs/nis/ntp server and a single node I am testing with. I have
plugged a laptop in to run wireshark and it gets an address from the
dhcp server fine. When the cluster node starts up and does the PXE
boot, the client receives its IP and loads the pxelinux.0 and kernel
image just fine over tftpd. When the kernel starts to boot and it
brings up networking, the client sends the DISCOVER but never receives
the OFFER even though the dhcpd server says it sent one and it just
worked fine for PXE on the same machine. There is no firewall on this
subnet, and since its working fine for both the laptop and PXE I am
lost as to why its not working for ipconfig. Here is the contents of
the dhcpd.conf file:

<code>
ddns-update-style none;
option domain-name "testing.com";
option domain-name-servers 192.28.1.11, 192.28.0.4;

default-lease-time 600;
max-lease-time 7200;

log-facility local7;

subnet 192.28.7.0 netmask 255.255.255.0 {
}


host node1 {
hardware ethernet 00:1e:c9:db:d3:b4;
fixed-address 192.28.7.114;
option host-name "node1";
option nis-domain "testing.com";
option nis-servers 192.28.7.3;
option ntp-servers 192.28.7.3;
option routers 192.28.7.1;
filename "pxelinux.0";
option root-path "/lustre/tmpboot/nodeimg";
}

host sniffer-laptop {
hardware ethernet 00:21:70:6c:36:fe;
fixed-address 192.28.7.10;
}
</code>

Here is the contents of syslog on the server:

Laptop connects fine...

<code>
Feb 28 11:35:38 gimmehservice-0 dhcpd: DHCPDISCOVER from 00:21:70:6c:
36:fe via eth0
Feb 28 11:35:38 gimmehservice-0 dhcpd: DHCPOFFER on 192.28.7.10 to
00:21:70:6c:36:fe via eth0
Feb 28 11:35:38 gimmehservice-0 dhcpd: DHCPREQUEST for 192.28.7.10
(192.28.7.3) from 00:21:70:6c:36:fe via eth0
Feb 28 11:35:38 gimmehservice-0 dhcpd: DHCPACK on 192.28.7.10 to
00:21:70:6c:36:fe via eth0
Feb 28 11:39:49 gimmehservice-0 dhcpd: DHCPREQUEST for 192.28.7.10
from 00:21:70:6c:36:fe via eth0
Feb 28 11:39:49 gimmehservice-0 dhcpd: DHCPACK on 192.28.7.10 to
00:21:70:6c:36:fe via eth0
Feb 28 11:44:31 gimmehservice-0 dhcpd: DHCPREQUEST for 192.28.7.10
from 00:21:70:6c:36:fe via eth0
Feb 28 11:44:31 gimmehservice-0 dhcpd: DHCPACK on 192.28.7.10 to
00:21:70:6c:36:fe via eth0
</code>

PXE client connects fine and loads the kernel image...

<code>
Feb 28 11:44:37 gimmehservice-0 dhcpd: DHCPDISCOVER from
00:1e:c9:db:d3:b4 via eth0
Feb 28 11:44:37 gimmehservice-0 dhcpd: DHCPOFFER on 192.28.7.114 to
00:1e:c9:db:d3:b4 via eth0
Feb 28 11:44:41 gimmehservice-0 dhcpd: DHCPREQUEST for 192.28.7.114
(192.28.7.3) from 00:1e:c9:db:d3:b4 via eth0
Feb 28 11:44:41 gimmehservice-0 dhcpd: DHCPACK on 192.28.7.114 to
00:1e:c9:db:d3:b4 via eth0
Feb 28 11:44:41 gimmehservice-0 dnsmasq-tftp[1182]: sent /ha/tftp/
pxelinux.0 to 192.28.7.114
Feb 28 11:44:41 gimmehservice-0 dnsmasq-tftp[1182]: error 0 TFTP
Aborted received from 192.28.7.114
Feb 28 11:44:41 gimmehservice-0 dnsmasq-tftp[1182]: failed sending /ha/
tftp/pxelinux.0 to 192.28.7.114
Feb 28 11:44:41 gimmehservice-0 dnsmasq-tftp[1182]: sent /ha/tftp/
pxelinux.0 to 192.28.7.114
Feb 28 11:44:41 gimmehservice-0 dnsmasq-tftp[1182]: file /ha/tftp/
pxelinux.cfg/44454c4c-4d00-1042-8051-b1c04f544731 not found
Feb 28 11:44:41 gimmehservice-0 dnsmasq-tftp[1182]: file /ha/tftp/
pxelinux.cfg/01-00-1e-c9-db-d3-b4 not found
Feb 28 11:44:41 gimmehservice-0 dnsmasq-tftp[1182]: file /ha/tftp/
pxelinux.cfg/AC1C0772 not found
Feb 28 11:44:41 gimmehservice-0 dnsmasq-tftp[1182]: file /ha/tftp/
pxelinux.cfg/AC1C077 not found
Feb 28 11:44:41 gimmehservice-0 dnsmasq-tftp[1182]: sent /ha/tftp/
pxelinux.cfg/AC1C07 to 192.28.7.114
Feb 28 11:44:41 gimmehservice-0 dnsmasq-tftp[1182]: sent /ha/tftp/
diskless/amd64/vmlinuz-2.6.32-5-amd64 to 192.28.7.114
Feb 28 11:44:42 gimmehservice-0 dnsmasq-tftp[1182]: sent /ha/tftp/
diskless/amd64/initrd.img.netboot to 192.28.7.114
</code>

From here the kernel boots, brings up networking and tries to get an
address and the server says its sending one:

<code>
Feb 28 11:45:11 gimmehservice-0 dhcpd: DHCPDISCOVER from
00:1e:c9:db:d3:b4 via eth0
Feb 28 11:45:11 gimmehservice-0 dhcpd: DHCPOFFER on 192.28.7.114 to
00:1e:c9:db:d3:b4 via eth0
Feb 28 11:45:12 gimmehservice-0 dhcpd: DHCPDISCOVER from
00:1e:c9:db:d3:b4 via eth0
Feb 28 11:45:12 gimmehservice-0 dhcpd: DHCPOFFER on 192.28.7.114 to
00:1e:c9:db:d3:b4 via eth0
Feb 28 11:45:13 gimmehservice-0 dhcpd: DHCPDISCOVER from
00:1e:c9:db:d3:b4 via eth0
Feb 28 11:45:13 gimmehservice-0 dhcpd: DHCPOFFER on 192.28.7.114 to
00:1e:c9:db:d3:b4 via eth0
Feb 28 11:45:14 gimmehservice-0 dhcpd: DHCPDISCOVER from
00:1e:c9:db:d3:b4 via eth0
Feb 28 11:45:14 gimmehservice-0 dhcpd: DHCPOFFER on 192.28.7.114 to
00:1e:c9:db:d3:b4 via eth0
Feb 28 11:45:15 gimmehservice-0 dhcpd: DHCPDISCOVER from
00:1e:c9:db:d3:b4 via eth0
</code>

This continues until the client gives up and errors out. But in
wireshark on the laptop, no DHCPOFFER packets are actually being sent
from the server, I only see the DISCOVER packets from the client. Any
reason why this would be happening?