connection to ":0.0" refused by server

[Alan DuBoff]

When I su to another user on the system (inside a terminal), I get the
following error when trying to run an X app:

----
Xlib: connection to ":0.0" refused by server
Xlib: Client is not authorized to connect to Server

Initialization error: X server not responding
: ":0.0"
----

I can do this on Red Hat, but not Debian.

How can I change this setting for Xlib?

-- 

Alan DuBoff
Software Orchestration, Inc.