xdmcp remote login, can log in to the server from one computer but not another

[Micha Feigin <michf@post.tau.ac.il>]

I'm trying to setup xdmcp login on one of my servers.

This server has two network interfaces (actually 4, but two active).

I'm trying to log in to X using xdmcp (enabled via gdm config) from two
clients, one connected directly via gigabit ethernet and the other over 100mb
network via an intermidiate switch.

The setup:

client one <--- (network) ---> server <--- (direct) ---> client two
132.66.40.189           132.66.41.26/192.168.1.1             192.168.1.2

client two connects with no problem. Client one sees the correct details for
the sever once it's given the address but hangs on connect (all I see is the
gray screen and the mouse cursor, nothing comes up)

The server is running gdm with xdmcp enabled, no firewall at the moment.

Any ideas?

Thanks