Actually, the 3D features were not discontinued with Acrobat 3D (which was the Acrobat 8 version with 3D capabilities). Adobe did rename the product (and add a bunch of other features) to Acrobat 9 Extended. However, as David mentioned starting with Acrobat X, the 3D authoring field was left to 3rd party developers. This means that you will have another expense to get software that can do this for you.
If you google for "3d pdf authoring", you'll find a lot of information about 3rd party products.
Karl Heinz Kremer
PDF Acrobatics Without a Net
PDF Software Development, Training and More...
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