I'd say your problem is more of a distro issue,
in that the method you are using to shutdown
is not actually requesting "poweroff".
That last mess above ("System halted.") comes from kernel_halt(),
rather than the expected message ("Power down.") from kernel_power_off().
So, try using the "poweroff" command instead of "halt",
or try using "halt -p". If neither of those work,
then edit /etc/init.d/halt and hardcode the "-p" parameter
inside there onto the "halt" command line(s).
I had to do that frequently back in the Redhat/Fedora days.
I'm sure they have a nice GUI for it somewhere,
but at the time it was simpler to just edit the script.
Cheers
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