ACPI: Battery Slot [BAT1] (battery absent)

[Marco]

Binary package hint: acpi

[ 0.472667] ACPI: Battery Slot [BAT1] (battery absent)
[ 1.560301] ACPI Warning for \_SB_.PCI0.SAT0.PRT0._GTF: Return type mismatch - found Integer, expected Buffer (20090903/nspredef-1006)
[ 2.200342] ACPI Error (dswload-0781): [_T_0] Namespace lookup failure, AE_ALREADY_EXISTS
[ 2.200350] ACPI Exception: AE_ALREADY_EXISTS, During name lookup/catalog (20090903/psloop-230)
[ 2.200356] ACPI Error (psparse-0537): Method parse/execution failed [\_SB_.BAT1.UBIF] (Node ffff88013ba2e100), AE_ALREADY_EXISTS
[ 2.200369] ACPI: Marking method UBIF as Serialized because of AE_ALREADY_EXISTS error
[ 2.200396] ACPI Error (psparse-0537): Method parse/execution failed [\_SB_.BAT1._BIF] (Node ffff88013ba2e0c0), AE_ALREADY_EXISTS
[ 2.200401] ACPI: Marking method _BIF as Serialized because of AE_ALREADY_EXISTS error
[ 2.200423] ACPI Exception: AE_ALREADY_EXISTS, Evaluating _BIF (20090903/battery-363)
[ 2.204307] ACPI Error (psargs-0359): [_T_0] Namespace lookup failure, AE_NOT_FOUND
[ 2.204314] ACPI Error (psparse-0537): Method parse/execution failed [\_SB_.BAT1.UBIF] (Node ffff88013ba2e100), AE_NOT_FOUND
[ 2.204352] ACPI Error (psparse-0537): Method parse/execution failed [\_SB_.PCI0.LPCB.EC0_._Q09] (Node ffff88013ba410e0), AE_NOT_FOUND

ProblemType: Bug
DistroRelease: Ubuntu 10.04
Package: acpi (not installed)
ProcVersionSignature: Ubuntu 2.6.32-22.33-generic 2.6.32.11+drm33.2
Uname: Linux 2.6.32-22-generic x86_64
NonfreeKernelModules: nvidia
Architecture: amd64
CheckboxSubmission: 88a98775d78448f97638aa764302e1cc
CheckboxSystem: ed86e29ffba809c116a39e33fa9fc45c
Date: Thu May 13 09:15:38 2010
ProcEnviron:
 LANGUAGE=it_IT:it:en_GB:en
 LANG=it_IT.UTF-8
 SHELL=/bin/bash
SourcePackage: acpi

[tuxsage (tuxsage)]

I have the same problem.
dmesg | grep batt
[ 0.974040] ACPI: Battery Slot [BAT1] (battery absent)

Bios is updated to the latest version and I am on Ubuntu 10.10 with kernel updated to the latest.