I just looked in the dmesg output when loading the thinkpad_acpi module and spotted this message. Maybe it helps?
[ 4565.175197] thinkpad_acpi: ThinkPad ACPI Extras v0.17 [ 4565.175203] thinkpad_acpi: http://ibm-acpi.sf.net/ [ 4565.175205] thinkpad_acpi: ThinkPad BIOS 7NET29WW (1.10 ), EC 7MHT24WW-1.02 [ 4565.175208] thinkpad_acpi: Lenovo ThinkPad X61s [ 4565.175595] thinkpad_acpi: radio switch found; radios are enabled [ 4565.185927] thinkpad_acpi: standard ACPI backlight interface available, not loading native one...
I just looked in the dmesg output when loading the thinkpad_acpi module and spotted this message. Maybe it helps?
[ 4565.175197] thinkpad_acpi: ThinkPad ACPI Extras v0.17 ibm-acpi. sf.net/
[ 4565.175203] thinkpad_acpi: http://
[ 4565.175205] thinkpad_acpi: ThinkPad BIOS 7NET29WW (1.10 ), EC 7MHT24WW-1.02
[ 4565.175208] thinkpad_acpi: Lenovo ThinkPad X61s
[ 4565.175595] thinkpad_acpi: radio switch found; radios are enabled
[ 4565.185927] thinkpad_acpi: standard ACPI backlight interface available, not loading native one...