Can I use annotaions (e.g. U3D) as part of an OCG Layer?

[Ivanho]

I would like to put some U3d content on a PDF Layer. I tried to add an “OC” key to the “Subtype=U3d” annotation dict, but Adobe Reader does not seem to take it into account. Is it possible ? Please could you tell me how to do it?

A: