So basically since you paid for both versions Quark will let you actually use both versions. Nice of them, eh?
Quark counts this move (which never should have been at issue to begin with) as one more feather in their oh-so-user-friendly cap, pointing to other changes they've made in the last 2 years like "Free English-speaking technical support" and "The ability to deactivate and re-activate or transfer a license of QuarkXPress 7 from one computer to another without the help of technical support." Call me old fashioned, but I kind of expect those things to begin with.
Still, I give them points for seeing the light on this one. Maybe they'll just stop making boneheaded decisions early on so they don't have to keep "changing their approach" midstream.