[ltp] can't detect cpu speed correctly on 600E

[davide]

I've got a slackware 9.1 on my thinkpad 600E (2645 3A0) and after a 
suspend (Fn F4) i couldn't have the full brightness on the screen. I 
rebooted and now the screen works fine, but the kernel (2.4.25) detects 
a 75 MHz cpu speed instead of 300 MHz (sigh!). I've recently installed 
Thinkpad 5.0, configure-thinkpad 0.1 and tpctl 4.10 and maybe I made a 
mistake with one of these, but I don't know.
Can anybody help me?
Davide