Freezes at shutdown and reboot

[Lion G.]

Hi all:

I see several messages on the mailing list
describing newer Acer laptops that
freezes at shutdown and at reboot.

I'm having the same problem (on an Acer Aspire 5050)

After "shutdown -r" and "shutdown -p"
umounts the drives, syncs, and prints uptime,
it just freezes right there.
(I tried setting hw.acpi.disable_on_reboot to 0 or 1,
and hw.acpi.handle_reboot to 0 or 1, in all 4 combinations
without any change in behavior)

I cannot disable ACPI, since the laptop won't even boot.

Does anyone have a suggestion on where to proceed?
Thank you!

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