X40 power on problem

[zaqrack]

Hello,
this is the 4th time my X40 produces the following problem:

-I commute by bike. I carry my laptop in my backpack safely attached.
-Sometimes the machine won't power on for a while (60-90mins)
-Symptoms are the same booting from battery/adapter, occur fast and quick:
-battery led green blink up
-num lock + caps lock simultaneously blink up
-power + battery + sleep led simultaneously blink up
(as far as I recall this is the standard blink process at normal boot)
and then off.
no HD nor fan noise, fan shakes some millimeters though

from adapter this occurs once, then no reaction for powering up until I reconnect the adapter
from battery only this occurs 1-5 times when I press the button again and again, then no reaction for powering up until I reconnect the battery

I tried laying it along with battery in/out, disassembling, booting upside down, pressing and holding power button for minutes, etc. Problem always disappears randomly after some minutes/hours.

It's annoying, as I would like to work right now too :-S Guess it's from shaking or cold (0-10 deg outside)? Is this some kind of self-protection of the machine? Couldnt find any documentation on it yet. How to prevent it or solve it?