well anything that stops them turning it off would just result in the battery being removed, there goes your chances of recovery! better to allow them to turn it off, but a script in the shutdown process sets the alarm for ten minutes and auto-reboots the phone, perhaps even reboot it an a way that it still appears off, yet continues to transmit gps etc.
They're maemo and MeeGo... "Meamo!" sounds like what Zorro would say to catherine zeta jones... after she slaps him for looking at her dirtily...