"can't open display" when connecting to a UNIX box

Dear all,

Here is my issue.
I’m using latest version 6.3.2 (to which I’m rather new) and am trying to open windows (nedit in my case) from a distant computer to which I connect.

telnet is OK.
I installed xPhoton and XFree86.
I export DISPLAY from the distant computer
i make xhost+ in a terminal.

I still get the error message:
“NEdit: Can’t open display”

Does anyone knows what I’m missing?

Thank you very much in advance for your help.