Originally Posted by
diezil
Well if there's no visable damage that you can see just by looking at the inside of the case ie: the plastic switch mechanisim, then try unscrewing the little tiny screw that holds the silver mirrored part on to the case, unclip that from the case and have a peek inside there to see if there's anything jamming the mechanisim, it can be fiddlly to get back together though, and there is a spring of sorts (not sure if its a spring or used to ground something).
Hope it helps you sort out the case :)