Unfortunately, we don't really have any better heuristics to check for what
makes up an installation although I'm open to ideas.  The current heuristic is
the one that's been used on upgrades for a long time.  We have improved the text
on the screen, though, so that it's less problematic

Well, is this case the heuristic is simple: 
if we didn't even managed to find out what version of Red Hat 
was installed (as I told you, the screen showed '' as the distro version) 
you can't upgrade it. 
And how about creating a file, something like /root/install-in-progress, 
that only gets deleted if the install really ends? 
I guess this is fixable, and will confuse newbie users if they screw 
an install and try reinstalling ("Neat, I can recover my failed install"). 

You could have just done `cat /dev/null > /etc/redhat-release`.  And,
unfortunately, a lot of "security" sites recommend doing just that :(

msf made the handling of this a little nicer.

I'm going through Bugzilla closing some bugs that have been marked as Modified
for some period of time.  I believe that most of these issues have been fixed,
so I'm resolving these bugs as Rawhide.  If the bug you are seeing still exists,
please reopen this report and mark it as Reopened.