Within a 48 hours of each other, two iPhone 4's on opposite sides of the world caught fire and self-combust. The first happened on 23 November on a plane over Australian skies and the second happened in Brazil where a slumbering Ayla Paulo Mota was rudely awoken when his iPhone 4 caught fire on his bedside table.

There are over 100 million iPhones in the world so don't worry too much about your phone combusting in your ear hole; 1:50,000,000 is a pretty good ratio by anyone's standards.

Unfortunately though, there still isn't conclusive evidence as to why these two phones managed to catch fire. There idea that malware is to blame for the iPhone overheating and exploding have been floated around the web, but such claims lack real substance.

This most plausible explanation for the iPhone's catching fire, seems to be a problem with the battery overheating combined with an insufficient cooling system in the device. The weight of this claim is blustered due to the fact that Apple has previous in the 'over-heating and catching fire' department - as it was reported that six iPods managed to catch fire in Japan last year and only three weeks ago, Apple recalled its first generation iPod Nanos sold between 09/05 and 11/06 due to fears that the batteries could catch fire.

The only sound advice we can give on the matter is to apply basic common sense and judgement. If you're iPhone 4 is feeling worryingly hot, you should turn it off and put it in a non flammable place. If it is a reoccurring problem, then contact your supplier.

Image courtesy of blogdoiphone.com