Backup for subdomains not working

[Atramasis]

I have updated Plesk to v12 and have a problem with the backup functionality. I have a subdomain that I created before the Plesk update and one subdomain created after the update. When I backup the subscription, only the new subdomain is backed up. At least I can not see the old folder when I try to restore "Files of domains" but the new subdomain folder is there. Is this a bug or do I miss something?