> Error: Invalid event handling mode: shutdown For the record: Xen has changed the way shutdown/reboot/crash behavior is specified in the domain config file (several times?). The quickest fix is to just delete lines related to shutdown/reboot/crash from /etc/xen/vm/plan9inst. If you want control over that behavior, check the relevant Xen documentation.
Like Ron says, QEMU, kvm, or lguest are better for running Plan 9. Stefan
