NIS Server can not work in unstable?

[phinex hung <phinex@hpcc.ee.nthu.edu.tw>]

Hello,

I am using unstable with kernel 2.4.2.
I try to setup my NIS server all day long, but still can solve my problem.
(It is a easy task when I using Redhat. )
I also lookup for the NIS HOWTO, but it does not say much about my question.
I also reference the steps in /usr/share/doc/nis to setup my nis Server, but 
still failed.

I am sure that the portmapper is working correctly.

% rpcinfo -p
 program vers proto   port
    100000    2   tcp    111  portmapper
    100000    2   udp    111  portmapper
    100004    2   udp    701  ypserv
    100004    1   udp    701  ypserv
    100004    2   tcp    704  ypserv
    100004    1   tcp    704  ypserv
    100009    1   udp    699  yppasswdd
 600100069    1   udp    704
 600100069    1   tcp    706

And when I type:
%rpcinfo -u localhost ypserv

The result is:

rpcinfo: RPC: Timed out
program 100004 version 0 is not available

While I use the following command:
# rpcinfo -u localhost yppasswdd
program 100009 version 1 ready and waiting


I really can understand how could this happen?
I also start ypserv in the debuggin mode, the message are:



Welcome to the NYS YP Server, version 1.3.11 (with securenets)]
Find securenet: 255.0.0.0 127.0.0.0
Find securenet: 0.0.0.0 0.0.0.0
ypserv.conf: dns: 0
ypserv.conf: 0.0.0.0/0.0.0.0:shadow.byname:2:0:2
ypserv.conf: 0.0.0.0/0.0.0.0:passwd.adjunct.byname:2:0:2
ypserv.conf: 0.0.0.0/0.0.0.0:*:0:0:2

I compare these with those produced by the "RedHat" machine, they are almost 
the same. 

I really confused this problem, can someone help me.
-- 
Sheng-Kai Hung          UIN: 10497781
E-mail: phinex@hpcc.ee.nthu.edu.tw
Dept. of Electrical Engineering, National Tsing Hua University