Apple has moved to at least partially answer user concerns about Apple iPhone handsets overheating by posting a newly revised document highlighting the overheating issues reported by some users - particularly those who have the new Apple iPhone 3GS.

However, Apple doesn't say if the new handset has overheating issues, which would clearly dampen potential sales and the document appears to be an update on one posted back in May, only now including the iPhone 3GS.

"If the interior temperature of the device exceeds normal operating temperatures, you may experience the following as it attempts to regulate its temperature: The device stops charging, display dims, weak cellular signal, temperature warning screen appears with the message 'iPhone needs to cool down before you can use it,'" Apple says in the document.

Apple suggests some fairly obvious remedies to keep your iPhone cool in hot weather.

"Store iPhone 3G and iPhone 3GS in a place where the temperature is between -20º and 45º C (-4º to 113º F). Don't leave the device in your car, because temperatures in parked cars can exceed this range."

"Operate iPhone 3G and iPhone 3GS in a place where the temperature is between 0º and 35º C (32º to 95º F). Low- or high-temperature conditions might temporarily shorten battery life or cause the device to temporarily stop working properly."

iPhone 3G and iPhone 3GS comply with the safety standard for Safety of Information Technology Equipment, IEC 60950-1 says Apple. This safety standard has been adopted by many countries.