Reflections picked up in multimatte?

[simmsimaging]

I might be crazy, but i thought there had been an update a while back and you could now get MatID's reflections showing up in multimatte render elements (to get a cheap and cheerful "alpha" for reflections). Am I remembering that wrong? Can't seem to figure out how to get it to work if not. I can do it other ways, but they require multiple renders which is a pain.

tks /b