Boehm-Demers-Weiser = Borg?

Strange, I thought it would be nice if I would add bindings to gc.h. But after thinking it over, what would happen: When garbage collecting the Boehm collector would travel the whole Hi heap looking for references to nodes allocated in the Boehm heap. So it might not be worth to have my own Cheney collector running in parallel with Boehm, even if faster?