Xmanager139 not login in AIX 4.3? [3]

The connection messages is "XDMCP connection failed.Try again"
I check the Xmanager.log,I find prompt:
XDMCP timed out, state 8
XDMCP timed out, state 8
XDMCP timed out, state 8
XDMCP timed out, state 8
XDM go to sleep: too many retransmissions

How should I config it?What files need to be modified?
Pls help me.

I found a lot of error messages in file /var/dt/Xerrors：
Sat Dec 27 19:57:21 2003
error (pid 72974): Hung in XOpenDisplay() attempt #0, aborting.

Sat Dec 27 19:57:21 2003
error (pid 72974): Server open attempt #0 failed for IP Address:0, giving up

Xmanager is a server software and it listens TCP ports 6000 ~ 6010. If your Windows machine is inside a firewall or has a private IP address, the remote X applications in AIX can't reach at Xmanager running on your Windows box.

Please check your network configuration first and try to run a "dtterm" program with Xstart.

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Technical Support

The question is ok,my client is in a firewall,I disable the firewall,the login interface is displayed.Thanks for your help!