As far as I know you only need SSO if you have multiple media servers, (at least this was the information given by one of our Principal Technology Specialists in year 2011/BE 2010 timeframe) as such you can share a Fiber Channel library betwen a NetApp using the NDMP Option and a single media server.
Best advice is zone everything in the library to both filer and BE media server and then let BE handle any contention issues. If harwdare parttioning is going to be used the the library MUST be capable of presenting a 'virtual' robotic arm to both media server and Netapp as we drive teh robotic commands via teh connectiopn being used for the backup - so NDMP data woudl be the filer moving the arm and Windows data would be the media server moving the arm.
BTW I know Hyper-V was mentioned and we have already said that the Hyper-V agent does not support SAN backups. However if you have Hyper-V in LUN's on the Netapp then you can backup the LUNs using the NDMP option but this is not recommended as you get no GRT cabability at all, which reduces you to a complete restore of the LUN only.
EDIT1: with regards the techniote informnation containing this text statuing "A library should not be shared between a filer and a Media Server, because the machine that accesses the library first will have ownership of it, and the other machine won't have access."
I am going to check but I believe this was an 11d statement (in effect version 1 of our NDMP option) and later versions of Backup Exec do not have this restriction. If I get confirmation of this I will get the tech artticle edited.
EDIT2: Our original release material for BackuP Exec 12.5 shows that we brought in library sharing between NDMP devices and media servers with this release. Please review the readme / release notes for 12.5 at
http://www.symantec.com/docs/TECH63281