Description of problem:
Because of another problem with Fedora-11-i386-DVD.iso, I am using
Fedora-11-i686-Live.iso for installation.  I had installed the Alpha
Fedora-12 from Fedora-12-Alpha-x86_64-DVD.iso with a boot partition
on sda3 before.  When it came to the boot configuration, I added
sda3 with the label Fedora_12_64, and re-named the label for the
new install with /boot on sda1 to Fedora_11_32.
The installer then reported an unexpected exception.  The backtrace said something about the label 'Fedora' .  When I re-tried without renaming
the label for the new install, the installer proceeded further without
exception.

Although I still have no working dual boot configuration,
but presumably that is a separate issue.
 
Version-Release number of selected component (if applicable):

As this was during install, exact information is hard to come by.
  
Actual results:

had to reboot without finished installation

Expected results:

should proceed with installation