USB Drive as iSCSI VTL? Pre-Sales Enquiry

I am looking at a few different NAS solutions, FreeNAS, Nexenta and Open-e DSS to use as iSCSI targets for MS DPM. My two key criteria are volume level replication from the master NAS to a remote NAS via WAN. They all do it, Open-e seems to be the least hassle of the three, my 2nd criteria is being able to present an attached 2TB USB drive as iSCSI Virtual Tape Library so DPM can use them as long term storage.

Nexenta does it with the help of a CLI tool, FreeNAS 8 has the option but it isn't implemented correctly (crashes the iSCSI subsystem) and Open-e is very vague around the subject although VTL is mentioned in the blurb.

Question; is Open-E capable of doing what I want and if so how to I set it up?

Thanks in advance, Peter.

This may help:
http://documents.open-e.com/Open-E_B..._USB_drive.pdf

The document shows me how to use a USB drive as a virtual tape to backup an Open-E NAS volume :( . I want to mount the USB drive as an iSCSI VTL so windows clients can connect to it as if it were a tape drive.

I suggest sending the windows backups to a NAS volume, then using the DSS VTL to make backups.
I USB drive can be used as a dynamic drive, but it will not be presented as a VTL to windows.

That would work except Microsoft Data Protection Manager doesn't use files to backup with. It uses disks (in this case iSCSI attached) carved up in to partitions for all its protected systems. It refuses to use USB as a destination but can use iSCSI tape - hence my need to mount the USB drive as a VTL over iSCSI :) Anything on the Open-E DSS road map that would enable this?

The dynamic drive could be used for a target, but DSS will not broadcast it as a VTL.