dmesg "ACPI Error: ...AE_NOT_FOUND..." --Should I be concerned?

The BIOS update solved the issue of activating the AMD-Vi IOMMU I described in /t/legacy-usb-iommu-conflict-in-opensuse-11-4-x86-64/73086/1. But there’s still one outstanding issue: while scrolling through the kernel ringbuffer looking for evidence that that the AMD-Vi (not GART) IOMMU was activated, I noticed the following error message in the ACPI section. I’m including a few extra lines before and after the error for context.

    0.426038] ACPI: Added _OSI(Module Device)
    0.426038] ACPI: Added _OSI(Processor Device)
    0.426038] ACPI: Added _OSI(3.0 _SCP Extensions)
    0.426038] ACPI: Added _OSI(Processor Aggregator Device)
    0.427108] ACPI: EC: Look up EC in DSDT
    0.428021] ACPI: Executed 2 blocks of module-level executable AML code
    0.433075] ACPI Error: [RAMB] Namespace lookup failure, AE_NOT_FOUND (20110623/psargs-359)
    0.433082] ACPI Exception: AE_NOT_FOUND, Could not execute arguments for [RAMW] (Region) (20110623/nsinit-349)
    0.433455] ACPI: Interpreter enabled
    0.433458] ACPI: (supports S0 S1 S3 S4 S5)
    0.433483] ACPI: Using IOAPIC for interrupt routing

If I understand correctly (highly likely that I don’t), the parser encountered an error in the AML code for an ACPI Environment object.

What I’m REALLY unsure about is whether this is something that I can safely ignore, or need to cajole the support techs at ASUS to get the BIOS fixed (or get a different motherboard).

Setup is as follows:
ASUS M5A99X EVO motherboard (AMD 990x/SB950 chipset)
AMD PhenomII x6 1100T CPU
Patriot Viper Extreme PC3-16000 2000 MHz memory, 8 GB (2 x 4GB)
Gigabyte ATI Radeon HD5670 1 GB DDR3 Graphics card
Thermaltake TR-2 430X power supply

Any guidance will be very much appreciated.