No, it was the most stupid mistake I would ever make. I was wondering how the VC 35 1.2 Nokton would look with an M2, so I placed a SLR lens on it to compare de size. I totally forgot that SLR lenses, as clunky as they are, have a more aggressive rear end, that touched the interior of the camera. Well, at least it didn't happen with a collapsible lens... so the curtain's fine.
Here's a crappy cell phone pic (sorry, I don't have digital cam right now). It's probably not as bad as it looks in the picture.
Thanks.