ssh and X forwarding

[H S Rai <hsrai@gndec.ac.in>]

On stable Debian installed PC, it appers that X is not 
allowed with ssh. As on issuing command:

	ssh -X ip.number1 gnome-terminal

it open a window, but issuing any command of graphic 
program, says:

> Gtk-Warning **: cannot open display

Same command for other PC (ip.number2 having RedHat9) opens 
the gnome-terminal without problem.

How I can allow ip.number1 to forward X?

--
H.S.Rai