[Users] sanlock leases on VM disks

I have an oVirt testing setup with 3 hosts running for a few weeks: CentOS 6.4, oVirt 3.3.1, VDSM 4.13.0, iSCSI based storage domain. I have just realized that sanlock has no leases on VM disks, so nothing prevents vdsm/libvirt from starting a VM on two different hosts, corrupting disk data. I know that something has to go wrong on oVirt engine to do it, but I've manually forced some errors ("Setting Host state to Non-Operational", "VM xxxx is not responding") for a "Highly available" VM and oVirt engine started that VM on another host. oVirt engine was not aware, but the VM was running on two hosts. I think this is a job for libvirt/sanlock/wdmd, but libvirt is not receiving "lease" tags for disks when creating domains. I think it should. What's left in my config? What am I doing wrong? Thanks