[libvirt-users] Two identical hosts, different capabilities and topologies

Hello, I've two twin servers (Dell PowerEdge R815) dedicated to kvm+libvirt and they have the same exact CPU (AMD Opteron(TM) Processor 6272) with the same topology (2 sockets, 16 cores per socket, so a total of 32 CPUs seen by the kernel) but both virsh -r capabilities and virsh nodeinfo say that the two machines are different - but they really are not! - and this prevents live migration from one server to another (but the other way round works). Attached you will find the output of some programs, if you need more info just ask. They are both running Debian Wheezy with latest backported kvm/libvirt (libvirt-daemon 1.2.9-6~bpo70+1). A curious fact is that kvm-host-01 detects the wrong topology (1 socket, 32 cores per socket) but it displays more capabilities, so migrating from kvm-host-02 -> kvm-host-01 works but from 01 to 02 fails. Any idea? Thanks in advance