[CentOS] NX and CentOS 5.5?

>I am running CentOS 5.5 in command line only.  Reason being I am standing up an IDS system on it.  
> 
>I have installed the NX client/node and server pkgs.  I have installed the NX client for windows on a Vista box.   When I attemtp to connect from the Vista to CentOS, I get this:

Huh? So no GUI, but you want NX? What's wrong with ssh?
You do realize NX is for remote desktop display?

Even if that works, you'd be using ssh to tunnel an ssh session?