Unity 3 - Oculus Rift support

I am already aware that OR requires a Pro version of Unity to function. What I wish to know is: is Unity 4.x mandatory? Or can it be used with Unity 3.x pro?

If Unity 4.x is mandatory, why is that? (Just out of pure curiosity)

Thanks in advance!

I just started working with OR, so apparently I don’t have enough karma to post a question on the official forum…

But I have yet to find any example using Unity 3.x (and have done a considerable amount of searching). The developer download page makes no mention of it as well (4 is quite specific), so I guess that the answer is “Yes. At the moment Unity 4.x is mandatory (for official support)”.

I’m going to close the question until further updates. However, since Oculus develops the library, I doubt they will worry about backward compatibility.