I finally got around to toying with NX server again on a Fedora 10 box.
Installing freenx-server on the server and nomachine's nxclient on the client side, things did not work out-of-the-box on my particular setup. On the server side,
/usr/libexec/nx/nxserver --adduser somebody
/usr/libexec/nx/nxserver --password somebody