Comment 1 for bug 782171

I wouldn't have thought that the keyboard issue is related to VirtualBox, as we simply emulate a standard PS/2 keyboard which should be handled in the kernel and transparent to the layers above. The X server crash might be - I assume that you have vboxvideo loaded into both servers, and having it running twice has been tested, but not extensively. On the other hand, I usually expect to see vboxvideo at least somewhere in the backtrace if it is related to the problem. If this is still relevant to you would you be able to tell us what version of the VirtualBox guest additions you have installed and provide Xorg.*.log files for both X servers? Note that we fixed a bug in version 4.1.4 of the Additions which can cause text console corruption when switching out of an X server.