Syslinux - Mar 2004 - about pxe booting, no boot filename found(cont.)

My /ect/dhcpd.conf looks like following:

# Sample /ect/dhcpd.conf
ddns-update-style ad-hoc;
allow booting;
allow bootp;

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

option subnet-mask 255.255.255.0;
option broadcast-address 10.0.0.255;
#option routers 10.0.0.1;
option domain-name "nfs.jun";

subnet 10.0.0.0 netmask 255.255.255.0 {
	range 10.0.0.1 10.0.0.100;
}

group {
	next-server server1;
	#next-server 10.0.0.1;

 	option vendor-class-identifier "PXEClient";
	#option dhcp-class-identifier "PXEClient";

	filename "/pxelinux.0";
	#filename "/tftpboot/pxelinux.0";

	host test1 {
	#next-server 10.0.0.1;
		hardware ethernet 00:A0:C9:99:B9:A8;
		fixed-address 10.0.0.2;
	}
}

My /ect/xinetd.d/tftp looks like following:
service tftp
{
	disable	= no
        socket_type             = dgram
        protocol                = udp
        wait                    = yes
        user                    = root
        server                  = /usr/sbin/in.tftpd
        server_args             = -u nobody -s /tftpboot/
        per_source              = 11
        cps                     = 100 2
	}

Please have a look of them, Thanks!
Chris