Prevent Encfs reverse mode from including other filesystems?

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http://askubuntu.com – I would like to use Encfs to encrypt a copy of / for a backup. Whenever I do this through other tools, they have an option to not cross filesystems. Is there an equivalent option in Encfs? Or would such attributes pass through to the encrypted version, and I should just run my backup tool with the one filesystem option? (HowTos)