I have a main Ubuntu system and a virtual Windows system, set up using QEMU/KVM. So, I can start Windows using virt-manager and connect to it using a VNC client.
But what I really want to have is a new Xorg display that is connected to this Windows system, so that e.g. CTRL-ALT-F8 shows Ubuntu, CTRL-ALT-F9 shows Windows. That'd be a real alternative to a Linux/Windows dual-boot setup.
I know that GDM had some option to connect to another X server (XDMCP), but I couldn't get this to work with GDM2/Ubuntu 10.4. Would this somehow also work to connect to a VNC server (like the virtual Windows system)?
I found many solutions on how to make Xorg provide a display for incoming VNC connections, but nothing on how to do the opposite.