I would like to allow another user to use CRTL+F2 to logon on another
gnome session. Any ideas, please?
It's not very clear why you want to do that (understanding why helps telling how), but here's my best shot.
This will start a gnome session in display :1, accessible with CTRL+ALT+F8.
su - other_user
# only users knowing the cookie can connect on display
xauth add :1 . `mcookie`
# start new display and run gnome session
xinit `which gnome-session` -- :1
Note `which gnome-session` may need to be expanded to the real path (ex /usr/bin/gnome-session or whatever). I had problems using `which` in the past.
That said, KDE
