Cannot use ACER 5051AWXMi when running on battery

Hi,
I own a ACER 5051AWXMi. I installed Kubuntu 7.10. I noticed that if I start my laptop with AC power X comes up with no issues.
However, if I run from battery power, as soon as boot completes and the login screen is shown the screen shows white artifacts.
Rebooting with ac power succeeds. This behavior is exhibited with the default video driver as well as the ATi driver (8.37.6).

I can confirm the same behavior on Kubuntu 7.04. I believe it has
something to do with power management. I have also noticed the following lines during boot(grabbed from dmesg):

[ 14.256245] ACPI: bus type pci registered
[ 14.272042] PCI: BIOS BUG #81[49435000] found
[ 14.272084] PCI: Using configuration type 1
[ 14.272086] Setting up standard PCI resources
[ 14.273379] ACPI: EC: Look up EC in DSDT
[ 14.274328] ACPI: EC: GPE=0x14, ports=0x66, 0x62
[ 14.295938] ACPI: System BIOS is requesting _OSI(Linux)
[ 14.295941] ACPI: Please test with "acpi_osi=!Linux"
[ 14.295942] Please send dmidecode to <email address hidden>
[ 14.296210] ACPI: Interpreter enabled
[ 14.296212] ACPI: (supports S0 S3 S4 S5)
[ 14.296223] ACPI: Using IOAPIC for interrupt routing
[ 14.299797] ACPI: EC: GPE=0x14, ports=0x66, 0x62
[ 14.299829] ACPI: PCI Root Bridge [PCI0] (0000:00)
[ 14.299835] PCI: Probing PCI hardware (bus 00)
[ 14.301540] PCI: Transparent bridge - 0000:00:14.4
[ 14.301647] ACPI: PCI Interrupt Routing Table [\_SB_.PCI0._PRT]
[ 14.301793] ACPI: PCI Interrupt Routing Table [\_SB_.PCI0.PB4_._PRT]
[ 14.301893] ACPI: PCI Interrupt Routing Table [\_SB_.PCI0.PB5_._PRT]
[ 14.301993] ACPI: PCI Interrupt Routing Table [\_SB_.PCI0.PB6_._PRT]
[ 14.302094] ACPI: PCI Interrupt Routing Table [\_SB_.PCI0.PB7_._PRT]
[ 14.302203] ACPI: PCI Interrupt Routing Table [\_SB_.PCI0.P2P_._PRT]
[ 14.302314] ACPI: PCI Interrupt Routing Table [\_SB_.PCI0.AGP_._PRT]
[ 14.304720] ACPI: PCI Interrupt Link [LNKA] (IRQs 10 11) *0, disabled.
[ 14.304830] ACPI: PCI Interrupt Link [LNKB] (IRQs 10 11) *0, disabled.
[ 14.304938] ACPI: PCI Interrupt Link [LNKC] (IRQs 10 11) *0, disabled.
[ 14.305045] ACPI: PCI Interrupt Link [LNKD] (IRQs 10 11) *0, disabled.
[ 14.305153] ACPI: PCI Interrupt Link [LNKE] (IRQs 10 11) *0, disabled.
[ 14.305261] ACPI: PCI Interrupt Link [LNKF] (IRQs 10 11) *0, disabled.
[ 14.305368] ACPI: PCI Interrupt Link [LNKG] (IRQs 10 11) *0, disabled.
[ 14.305476] ACPI: PCI Interrupt Link [LNKH] (IRQs 10 11) *0, disabled.
[ 14.305583] ACPI: PCI Interrupt Link [LNKU] (IRQs 3 4 5 7) *0, disabled.
[ 14.305655] Linux Plug and Play Support v0.97 (c) Adam Belay
[ 14.305664] pnp: PnP ACPI init
[ 14.305672] ACPI: bus type pnp registered
[ 14.307441] pnp: PnP ACPI: found 10 devices
[ 14.307443] ACPI: ACPI bus type pnp unregistered
[ 14.307446] PnPBIOS: Disabled by ACPI PNP
[ 14.307485] PCI: Using ACPI for IRQ routing
[ 14.307487] PCI: If a device doesn't work, try "pci=routeirq". If it helps, post a report
[ 14.307493] PCI: Cannot allocate resource region 7 of bridge 0000:00:04.0
[ 14.307537] PCI: Cannot allocate resource region 8 of bridge 0000:00:04.0
[ 14.307577] PCI: Cannot allocate resource region 7 of bridge 0000:00:05.0
[ 14.307616] PCI: Cannot allocate resource region 8 of bridge 0000:00:05.0
[ 14.307655] PCI: Cannot allocate resource region 7 of bridge 0000:00:06.0
[ 14.307694] PCI: Cannot allocate resource region 8 of bridge 0000:00:06.0
[ 14.307733] PCI: Cannot allocate resource region 7 of bridge 0000:00:07.0
[ 14.307771] PCI: Cannot allocate resource region 8 of bridge 0000:00:07.0

Please advise as there seems to be no way of running the laptop on battery.

I could run PCLinuxOS(with default video driver) on battery as long as I did not run any OpenGL applications.
Upon installing ATi's driver the same behavior as in the case of Kubuntu was noticed.

This issue confines the use of my laptop to my desk. Please help.

Regards,
Anup