[ovirt-devel] Thin provisioning??

Hi, I've migrated few Linux VM's from virt-manager to oVirt. Other than the famous bug that it insist to have an ISO domain - it worked well. My problem is simple: on virt-manager, I created the virtual disks as thin provisioning. ls -l shows the full size of the QCOW2 file and du -hs shows the actual size. So far, so good. After migrating those VM's to oVirt, the disks appear both in the web UI and in the meta file as "Thin Provisioning" and "sparse" - however, digging into the directory which holds the virtual disk and running du -hs - shows it's a full size disk. Why is this happening? (the storage on the oVirt is NFS)