The problem might not be a Xinerama problem. I got the same issues when using fake-Xinerama (I used ldd /usr/sbin/gdm to make sure it was loading the right .so file.)
I got Twinview to treat my vertical monitors properly, and I used fake Xinerama to patch them together. I still got issues with "Invalid input device pointer". If I use fake Xinerama without Twinview (four screens), I still get errors. I think that the issue has much to do with the physical arrangement of monitors and the number of screens. I had my screens configured in such a way that Monitor 0 and Monitor 2 were on one card, and Monitors 1 and 3 were on the other (I wanted both my large DFPs to have DVI inputs.) If I plug the screens in such that Monitors 0 and 1 were on one card, and Monitors 2 and 3 on the other, the issues seem to go away somewhat. -- [multi screen] mouse position sometimes wrong https://bugs.launchpad.net/bugs/363375 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs