tpfan-admin won't start

Hi
I used tpfanadmin for a long time. One day it didn't start anymore. After that I removed it (purge) and installed it again, but that didn't help. I would say I didn't change anything, but why souldn't it work anymore.
The only thing I want to do is to change from HW-control to full-speed sometimes.
My system is a ubuntu 8.04 with a 2.6.24-23-generic kernel on a T61-6462-A49.

Thanks
Stefan

Output when started from console:

Traceback (most recent call last):
  File "/usr/bin/tpfan-admin", line 23, in <module>
    tpfanadmin.globals.init()
  File "/usr/lib/python2.5/site-packages/tpfanadmin/globals.py", line 111, in init
    read_preferences()
  File "/usr/lib/python2.5/site-packages/tpfanadmin/globals.py", line 35, in read_preferences
    temperature_dialog.set_temperature_unit(unit)
  File "/usr/lib/python2.5/site-packages/tpfanadmin/temperaturedialog.py", line 333, in set_temperature_unit
    raise ArgumentException()
tpfanadmin.temperaturedialog.ArgumentException