CLOUDSTACK-2823: This affects Ubuntu as well, since qemu version is 1.0.0
I don't think host kernel version has any bearing on it. Original code
was tested with CentOS 6.3 and 6.4, but it seems to succeed or fail per-host,
e.g. a fast host might work and a slow host might not. I was getting intermittent
failures with ubuntu 12.04.3 prior to this patch.