Contributed by Davide Giunchi Italian version: http://www.soasi.com/2013/06/backup-axigen-mail-server-con-bacula-e-bacula-enterprise/
Axigen is “groupware” mail server with calendar and collaboration functionalities, archives are stored in /var/opt/axigen/domains, they are binary archives in a proprietary format, you can't run correctly incremental/differential backup and even backup and restore single mailboxes or domains.
Axigen provide an FTP interface, with this interface you can access to the domain and mailboxes data and run backup and restore of the single mailboxes. On Linux server you can automate FTP access with FUSE (filesystem in user space), mount ftp access and then backup as normal directory/files.
WORK IN PROGRESS!!!