I think thinkpad_acpi module overrides/hides the settings of last bluetooth power state (always on) since on my asus eeepc it works fine (turn off bluetooth via applet -> reboot -> it stays turned off and vice versa it also works fine).
In Ubuntu 11.04 Natty there is the same problem (bluetooth always on) with thinkpad t500!
I think thinkpad_acpi module overrides/hides the settings of last bluetooth power state (always on) since on my asus eeepc it works fine (turn off bluetooth via applet -> reboot -> it stays turned off and vice versa it also works fine).
In Ubuntu 11.04 Natty there is the same problem (bluetooth always on) with thinkpad t500!