A third Nokia phone explosion seems to confirm the cheap battery explanation

A Thailand company executive had a surprise this week when his phone exploded in his hand, throwing shrapnel over a radius of 3 metres. In other cases earlier this year, Nokia blamed cheap third party batteries for the explosion and it smells bad here too: the phone's owner says he suspects his battery since he bought it from a discount dealer in Bangkok and "paid far less than normal for a genuine Nokia accessory". (source)