XDMCP connection failed from window 2000 Pro [1]

The linux box (running RedHat 8.0) can be accessed from a PC running Window Pro Home. However, it failed from Window 2000 Pro.

There are some hints:
1. I can ping the linux box from window 2000 Pro, and vice versa.
2. I can see the linux box from XBrowser with correct IP address.
3. there is an error message in the log file (detailed attached below)

Xdmcp: sent a MANAGE message.
Xdmcp: Timed out, state 8. Retransmissions: 3

Can anybody help?

Many thanks.

Stephen

==============================================

=== OS Version Information ===
Platform id : 2
Major Version : 5
Minor Version : 0
Build Number : 2195
Description : "Service Pack 2"
Country Code : 1
Country String: United States
==============================
Xdmcp Request Address: 192.168.1.104
Xdmcp Connection Address 0: 192.168.1.103
Xdmcp: sent a REQUEST message
Xdmcp: received an ACCEPT message
Xdmcp: sent a MANAGE message.
Xdmcp: Timed out, state 8. Retransmissions: 0
Xdmcp: sent a MANAGE message.
Xdmcp: Timed out, state 8. Retransmissions: 1
Xdmcp: sent a MANAGE message.
Xdmcp: Timed out, state 8. Retransmissions: 2
Xdmcp: sent a MANAGE message.
Xdmcp: Timed out, state 8. Retransmissions: 3
XDM go to sleep: too many retransmissions

The problem may occur when:

• The DNS system in Linux maps the IP address of your W2k into an incorrect name, or vice versa. You need to check the DNS lookup tables to verify it.
• The firewall system in your W2k is enabled and incoming connections are not allowed. You should be able to ping 2000 Pro from the Linux box.

Hope to solve the problem.

----
Technical Support