Backup Manager doesn't clean /var/lib/psa/dumps

[FilipeS]

I've configured the "Backup Manager" to backup up my domain to a "Personal FTP Repository":

- Backup period: daily
- Start backup creation at (HH:mm): 2h00
- Personal FTP repository: selected
- Maximum number of backups in repository: 5
- Back up: Domain configuration and content

However some time after my machine's disk got full and I've discovered that /var/lib/psa/dumps is full of dump files...

Is this a bug or there is some way to change this behaviour?
(I don't have nothing configured to local server repository)