Need to extract information of color bleeding on shapes in Mental ray

[machasone]

hi gods and goddesses,

I am wondering if there are any ways to extract information of color bleeding on shapes and add it to a new render pass in Mental ray without turning the shapes' primary visibily off.
to help yourself understanding what I am talking about, please see the greencircle in the attached image.
that's the one I would like to extract.

I am using Maya 2011.
Thank you very much for your help in advance.

Machasone