Comment 1 for bug 501305

You failed to identify what distribution you are using and what version as well as which ppa you have used for your packages. We need the architecture as well are you using the 32bit or 64bit version? You also have not specified whether you are using Gnome, KDE or some other desktop environment. It sounds to me like your window decorations are not installed, but without further information I am just guessing. You also have not identified what works on a local login. You also have not specified whether you are even using Ubuntu.

Please submit results of:
uname -a
nxserver --help

And reply to the above questions.