In IMT, For OSSV:
Under Windows Server 2008, There are 4 catagoies:
1. DCE
2. EE
3. R2
4. SE
Now, under R2, If you click 'EE' and select 64bit, x64 specifically (Or even if you select 'R2' at root), then look at NetApp Host Agent, it is grayed out.
Whereas, If I select Windows Server 2008 at the ROOT. Then, NetApp Host Agent is selectable for 2.7.