That means that you get for example an xterm working (graphically) in your OS X box? This means that it opens an new window in your local graphic X system and you can move it, etc.
if yes, I will suggest you to read Bruno's instruction on installing oracle in redhat 7.x, it needs a special configuration to get it working, check it here
http://archive.greenpeace.org/~bruno/oracle.html .
if not, your are not still tunneling X through ssh.
