[development] Taking over a module

I would like to take over a module that's currently in contrib, in this case profile_pages. I've contacted the maintainer, PyromanFO, and he's happy to let me do so, but neither of us know what to do next. I did some searching, because I'm sure this process is documented somewhere, but I couldn't find anything. So, does anyone know how this is done? // Jeff Beeman