This is exactly why I don't use lightroom in my studio, other than this one issue, oh and CMYK, it rocks. On CMYK, even if there was just a way to track files in lightroom, ie, have the raw in the catalogue, and all of the virtual copies, and RGB tif's AND the CMYK tif's that you have worked on in Photoshop. I can live without being able to actually do anything to them, but at-least have everything all together. At the moment everything is all neat and tidy and in one place, except all the CMYK images that get sent to clients.
Yes I know Martin Evening has a kind of workaround, but it is a pain, and should be implemented in the program ASAP.
Cheers.