Alpha Transparency in Rotation animation

I am not sure if this is a simple question or not but there must be an easy way to do this in a quick and painless fashion. I am rendering an animation of a simple object in a 360º rotation. The end result is going to be used in a flash animation so I need the background of every frame of this rotaion (whether in movie or image sequence format) to be transparent. The old way I used to do it is a wicked pain (each frame being edited by hand using an additionally rendered mask sequence in a seperate file). Is there a composite setting or some tag I may apply to the object to make this happen? If not, is there a simple workflow to accomplish making the background of each frame transparent?
Hope I described this clear enough.

Thank you very much for your time and any help I can get from you all.

•MAH•

Nevermind...I'll do more research and figure it out like I always do.

Cheers

Just enable the multipasses and use an object ID on your object. You can then use that object ID to generate the alpha automatically in your compositing application.

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