Hi,
normaly there should be an entry like:
2011-04-26 22:00:07,374 INFO [btpool0-87647] [name=zimbra;ip=127.0.0.1;] backup - Incremental backup started for backup set; label: incr-20110426.200007.372
2011-04-26 22:00:07,669 INFO [btpool0-87647] [name=zimme@domain.ag;mid=346;ip=127.0.0.1;] backup - Incremental backup is started for account
zimme@domain.ag
2011-04-26 22:00:07,669 INFO [btpool0-87647] [name=zimme@domain.ag;mid=346;ip=127.0.0.1;] backup - Saving account information from LDAP
2011-04-26 22:00:07,831 INFO [btpool0-87647] [name=zimme@domain.ag;mid=346;ip=127.0.0.1;] backup - Incremental backup has ended
but there is nothing within mailbox.log.
best regards
thomas