drobo and lion encrypted time machine

Drobo and osx lion. I tried the encrypted time machine, but it gives errors.
Is it supported or will it be supported ?

Encrypted backups are interesting.

Full disk encryption on thin-provisioned volumes (e.g a 16TB volume on a Drobo with only 3TB of physical space) is a big problem in general. The encryption tries to write to every sector, but you don’t have physical disk behind all the virtual sectors so it falls over.

You would have to have a separate partition that is less than your physical space, or use a sparseimage type of solution.