In openSUSE 11.1, how would I add a customized desktop environment/window manager/X session to the list of selectable logins? So far, I have GNOME, KDE4, TWM, wmii2, and IceWM available from GDM. But I'd like an alternate GNOME with Icewm replacing metacity for the window manager, while still being able to login to the original GNOME. Or Icewm+Nautilus desktop. So, from GDM I'd have a choice of GNOME, GNOME + IceWM, IceWM, IceWM + Nautilus, etc.

The last time I did this was on another Linux distro and earlier X version; things seem different here.