Backup to NAS device - does it require Virtual disk license?

Hello,

My company is looking at buying BE 2012 and a NAS for a backup solution rather than an LTO-tape system.

We were told that for BE 2012 to backup to a NAS device that we need to use a virtual tape drive and license since BE normally backs up to tape devices. 

The NAS would be the target location for backups, NOT what we'd backup. 

Is this how it's done or is there any other way? The license fees for a virtual drive to a NAS were pretty steep so it made us wait on our purchase. 

I saw this link but it's referring to SAN units. What we have is much smaller scale:

http://www.symantec.com/business/support/index?pag...

Any advice would be greatly appreciated.

Thank you!