vzdump suspend mode problem - xfs on /var/lib/vz

Hello,


I have mounted different device into my /var/lib/vz directory than the default one (better,faster..).
I have xfs filesystem on this device.


Since than have my vzdump backup using mode suspend stopped to work:


vzdump XXX --mode suspend --storage backup


....
INFO: Can not suspend container: Invalid argument
INFO: Error: unsupported fs type xfs
INFO: Checkpointing failed
ERROR: Backup of VM XXX failed - command 'vzctl --skiplock chkpnt XXX --suspend' failed: exit code 16
INFO: Backup job finished with errors


Is it because of the xfs filesystem on /var/lib/vz?
Is it possible add xfs support somehow?
If I change it to ext3, should it wok correctly without LVM?


I use 2.3 Proxmox.


Thanks, Petr