Thanks to sss and Mike for the addition of the Zimbra version check on the script. I moved it down to after the second rsync so as to not have it blown away in the rsync, while preserving the ability of --delete to get rid of the temp files that would otherwise be left over from the first live rsync.
Mike's idea of rsnapshot is an interesting one that could take the shell script from single-backup to a whole incremental stack. I don't have time to play with it now but it's certainly worth exploring!
