"Unable to start the ACPI Interpreter" in 2.6.16

Hi,

A Gentoo user reported a 2.6.16 regression at http://bugs.gentoo.org/129011

In a nutshell, ACPI worked in 2.6.15, and breaks in 2.6.16 and the /proc/acpi interface is not present. Here are the relevant looking messages from dmesg:

ACPI: SCI (IRQ0) allocation failed
ACPI Exception (evevent-0167): AE_NOT_ACQUIRED, Unable to install System Control Interrupt handler [20060127]
ACPI: Unable to start the ACPI Interpreter
evxfevnt-0134 [06] disable : ACPI mode disabled
ACPI (utalloc-0862): No outstanding allocations [20060127]
ACPI Exception (utmutex-0257): AE_BAD_PARAMETER, Thread 1 could not acquire Mutex [6] [20060127] ACPI Exception (utmutex-0257): AE_BAD_PARAMETER, Thread 1 could not acquire Mutex [6] [20060127]

Full dmesg can be found at http://bugs.gentoo.org/attachment.cgi?id=84551&action=view

This bug is already fixed in 2.6.17-rc1. Does anyone know offhand which patch fixes this? I'd like to backport the fix and also submit it for the -stable branch.

Thanks,
Daniel