remote x via ssh question

[Forrest English <forrest@truffula.net>]

i know i can export it just like i would any other time, but i also set X11Forwarding yes, which i belive should
forward it automaticaly, and here's what i recive when i try and run

[forrest@truffula forrest]$ xterm
xterm Xt error: Can't open display:

(this is from my other box, which is a mandrake machine).   it seems to be the same thing that happens when i try and
run an application localy as root while using x as user.    so, i guess i'm wondering how i'd fix that too.   are there
some permisions that need to be set correctly, so that i can run applications as a user other than the user that is
currently using x?

-- 
Forrest English
http://truffula.net

"I don't like this air, but that doesn't
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