Creating instance fails on oneiric

Using the instructions in https://github.com/vishvananda/novascript, things work fine when using lucid, but creating an instance does not work on oneiric. The error is

libvir: QEMU error : internal error Process exited while reading console log output: chardev: opening backend "file" failed

lucid seems to be using libvirt-bin version 0.8.8-1ubuntu3~ppalucid1 while oneiric uses 0.9.2-4ubuntu13

Here is the transcript:

2011-09-14 16:11:16,305 DEBUG nova.utils [-] Running cmd (subprocess): sudo qemu-nbd -c /dev/nbd15 /root/nova/instances/instance-00000001/disk from (pid=11656) execute /root/nova/nova/utils.py:165
2011-09-14 16:11:17,321 DEBUG nova.utils [-] Running cmd (subprocess): sudo tune2fs -c 0 -i 0 /dev/nbd15 from (pid=11656) execute /root/nova/nova/utils.py:165
2011-09-14 16:11:17,932 DEBUG nova.utils [-] Running cmd (subprocess): sudo mount /dev/nbd15 /tmp/tmpnvONQd from (pid=11656) execute /root/nova/nova/utils.py:165
2011-09-14 16:11:18,006 DEBUG nova.utils [-] Running cmd (subprocess): sudo mkdir -p /tmp/tmpnvONQd/root/.ssh from (pid=11656) execute /root/nova/nova/utils.py:165
2011-09-14 16:11:18,016 DEBUG nova.utils [-] Running cmd (subprocess): sudo chown root /tmp/tmpnvONQd/root/.ssh from (pid=11656) execute /root/nova/nova/utils.py:165
2011-09-14 16:11:18,027 DEBUG nova.utils [-] Running cmd (subprocess): sudo chmod 700 /tmp/tmpnvONQd/root/.ssh from (pid=11656) execute /root/nova/nova/utils.py:165
2011-09-14 16:11:18,037 DEBUG nova.utils [-] Running cmd (subprocess): sudo tee -a /tmp/tmpnvONQd/root/.ssh/authorized_keys from (pid=11656) execute /root/nova/nova/utils.py:165
2011-09-14 16:11:18,047 DEBUG nova.utils [-] Running cmd (subprocess): sudo umount /dev/nbd15 from (pid=11656) execute /root/nova/nova/utils.py:165
2011-09-14 16:11:18,774 DEBUG nova.utils [-] Running cmd (subprocess): rmdir /tmp/tmpnvONQd from (pid=11656) execute /root/nova/nova/utils.py:165
2011-09-14 16:11:18,780 DEBUG nova.utils [-] Running cmd (subprocess): sudo qemu-nbd -d /dev/nbd15 from (pid=11656) execute /root/nova/nova/utils.py:165
libvir: QEMU error : internal error Process exited while reading console log output: chardev: opening backend "file" failed
2011-09-14 16:11:24,290 ERROR nova.exception [-] Uncaught exception
(nova.exception): TRACE: Traceback (most recent call last):
(nova.exception): TRACE: File "/root/nova/nova/exception.py", line 98, in wrapped
(nova.exception): TRACE: return f(*args, **kw)
(nova.exception): TRACE: File "/root/nova/nova/virt/libvirt/connection.py", line 599, in spawn
(nova.exception): TRACE: domain = self._create_new_domain(xml)
(nova.exception): TRACE: File "/root/nova/nova/virt/libvirt/connection.py", line 1203, in _create_new_domain
(nova.exception): TRACE: domain.createWithFlags(launch_flags)
(nova.exception): TRACE: File "/usr/lib/python2.7/dist-packages/libvirt.py", line 372, in createWithFlags
(nova.exception): TRACE: if ret == -1: raise libvirtError ('virDomainCreateWithFlags() failed', dom=self)
(nova.exception): TRACE: libvirtError: internal error Process exited while reading console log output: chardev: opening backend "file" failed
(nova.exception): TRACE:
(nova.exception): TRACE:
2011-09-14 16:11:24,292 ERROR nova.compute.manager [-] Instance '1' failed to spawn. Is virtualization enabled in the BIOS? Details: internal error Process exited while reading console log output: chardev: opening backend "file" failed
(nova.compute.manager): TRACE: Traceback (most recent call last):
(nova.compute.manager): TRACE: File "/root/nova/nova/compute/manager.py", line 424, in _run_instance
(nova.compute.manager): TRACE: network_info, block_device_info)
(nova.compute.manager): TRACE: File "/root/nova/nova/exception.py", line 129, in wrapped
(nova.compute.manager): TRACE: raise Error(str(e))
(nova.compute.manager): TRACE: Error: internal error Process exited while reading console log output: chardev: opening backend "file" failed
(nova.compute.manager): TRACE:
(nova.compute.manager): TRACE: