Starting problem - Pajero

Hi all,

I have a 1996 Pajero V6 3500.
Every once in a while, after I've driven it for a few miles/km - stopped the engine - waited for a few minutes it won't start.
The engine cranks and for a brief moment it fires up and then stops. After that it just wont start. I have to wait for 5-10 minutes and then it fires up without any problems.

I'm suspecting the electronic start prevention system (hmm don't know the english term for it) wich prevents the engine from firing up if the correct key isn't in the switch.

But the strange thing is, this only happens after short trips where I stop the engine and then want to start it up again a few minutes later. Never from a cold start.

Has anyone experienced similar problems .. or know where to start looking .. ?

Thanks,
Ozeki