Most recent kernel where this bug did not occur: Distribution: Hardware Environment: Software Environment: Problem Description: Steps to reproduce: System: Amilo m1439g with Sarge Debian It is possible to control the cpu frequency, but it is not possible to control fan speed and cooling_mode. The directory /proc/acpi/fan is empty.
Please, send the output of dmesg, acpidump. It is possible that your system doesn't have APCI fan control.