[reacweb]

I have already encountered the need for multiheaded system. I wanted to run a second X server on my third screen in order to have a separate mouse. I have not found any website explaining this kind of setup. I have never succeeded: the mouses were active on both X servers.

[dsr_]

You need to have a separate xorg.conf for your separate X instance. (Edit) and you need to hardcode each device, not allow autodiscovery.