With older gnome-session versions, it was possible to use gnome-session for starting gnome and fvwm using the --choose-session option of gnome-sessions.

But with current gnome-session versions, that doesn’t work anymore. The --choose-session option is gone, and it is a --default-session-key. But I didn’t find any example of its use, and the only doc I found was in “man gnome-session”, and it doesn’t even tell if this option can be used for what I want to do, or if it is only for different gnome sessions.

I was able to run fvwm with gnome-session, by just running “gnome-session”. The obvious conclusion is than gnome-session will start fvwm if I want to start gnome.

In order to get back gnome, I must delete ~/.gconf and ~/.config/gnome-session/saved-session. After that, in order to run fvwm with gnome-session, I have to run gnome again and configure it to run fvwm and forget about gnome.

Is it some way to use current gnome-session to start both fvwm or gnome?

I found it. It is just to make a directory (as example ~/.gnome-session) with a desktop file with something like:

[code][Desktop Entry]
Comment=Umm… Nice desktop. Transparent, and all…

[Window Manager]
and put

exec ck-launch-session gnome-session -a ~/.gnome-session

in ~/.xinitrc

The only problem I found with this is when you quit, from the gnome menu, a nested gnome session, fvwm will quit at the same time.

But it is another problem. With the first solution, gnome-session-save is working. With the second one, it save nothing at the exception of fvwm.