[libvirt-users] Is it possible to live migrate guest OS'es between different versions of kvm/qemu-kvm with libvirt?

Hi, I currently have a couple of Debian KVM servers with all a different version of kvm or qemu-kvm. I can live migrate a guest OS from one server to the other just fine, as long as the version of qemu-kvm is the same. However, when I try to migrate a guest to a server running a newer (or older) version of qemu-kvm, I run into problems. I think this is because the xml configuration differs slightly between version. For example, if I try to migrate from a server running qemu-kvm 0.11.0 to one running qemu-kvm 0.12.4, I get the following error: virt01:~# virsh migrate --live testserver qemu+ssh://192.168.1.7/system error: internal error unable to reserve PCI address 0:0:3 When migrating from kvm 85 to qemu-kvm 0.11.0: virt02:~# virsh migrate --live testserver qemu+ssh://192.168.1.2/system error: Unknown failure Migrating one from 0.12.4 to 0.11.0 just completely breaks libvirt, forcing me to kill -9 libvirtd and the kvm instance, etc. I believe this is caused in part because different versions of qemu-kvm need different xml configurations. To run my testserver on 0.12.4 for example, I need to delete the lines with the PCI id's, just to be able to start it. So, is there a way to make this work? Perhaps tell libvirt to not send the config file when doing a live migrate, and use the xml in /etc/libvirt/qemu instead somehow? Thanks in advance, Nils