Remote Gnome session in nested window

I needed to access remote Gnome session (actually a JDS session) to try something with the settings. That is - I needed something like the "Remote desktop" setup on Windows. One way is to setup VNC (but that's extra effort with no sense). Second might be IPsec with XDCMP or and VPN (ok, even more extra effort...). So the chosen way was to tunnel X through ssh.

To do this with a standalone X server, you need to start X, run SSH with correctly set up display and start gnome-session script on the remote side.

1. Way:
   xinit -e 'ssh -X who@where gnome-session' -- :1
   This works reasonably, but always somewhere have the "login window" where the gnome-session was started. Pro - you see the errors, con - if you close it, the session dies.
   
2. Way:
   Add xauth data for the display, then start a nested X server and then xterm, which starts a SSH session and exits then. The SSH session keeps running on background and the session looks "normal"
   
   xauth add :1 `xauth list | grep localhost.localdomain/unix:0 | cut -d ' ' -f 2-`
   Xnest -auth .Xauthority :1 -geometry 1024x700 & xterm -display :1 -e ssh -X -f bobr7.fjfi.cvut.cz gnome-session
   
3. The same, just with normal X-server, not Xnest. Maybe a delay will be needed before X-term start?

Further reading:

1. http://www.technovelty.org/linux/tips/xnest.html