I have the same problem, gnome-terminal refuses to start with Xinerama on. Although, I am able to launch it if I set the environment variable XLIB_SKIP_ARGB_VISUALS set to true:
XLIB_SKIP_ARGB_VISUALS=1 gnome-terminal -- gnome-terminal does not start when using xinerama and nvidia https://launchpad.net/bugs/58232 -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
