For some reason, I cannot convince the app store that an application (Xcode, in this case) is not installed.
I have deleted /Developer (which only contained an old, busted Xcode 3.2.3) and tried to rebuild the LaunchServices DB (using lsregister -kill -r -domain local -domain system -domain user
) but to no avail; The app store stubbornly claims that Xcode is already installed.
I'm at my wit's end, here.