[X-Unix] Displaying windows over the network

[KL Tah]

Hi all,
I have a question about displaying windows on my machine in X11 when I'm
logged in to a remote machine with several layers of remote machines beneath
it.

If I'm logged onto say remote_machine_1, using
Ssh -X remote_machine1,
I can open xterm fine on my mac.

The problem is that once on remote_machine1, if I do another ssh -X
remotemachine2 say, I can't open a window from that machine even after
setting the display environment. Output looks something like that:
Remote_machine2:mydir% xterm &  <--(seems fine here, but moments later...)
[2] 18152
Remote_machine2:mydir% xterm Xt error: Can't open display: xxx.xxx.x.x:0

Where I have replaced my ip_address with x's.

Thanks,
KL

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