Nope its not a Windows Mobile, not Vista not XP not even 98.(click link below for pics and full story)
Its Windows 3.1! The OS that made Microsoft what it is today has been ported to run on Symbian OS. How? Via DOSBox, it has been available for quite sometime but only recently have we seen it run on a Nokia N95. Some Polish dude was brave enough to do this. Hmmm makes me jealous, now to find someone who knows Polish so that we can duplicate what he did.