One of the main characteristics of giftedness, based on my understanding, is to be more intense or extreme - and emotionally intense is not an exception. As a matter of fact, somewhere along the way I came across an understanding that the higher the IQ, the more intense the "special" characteristics. Of course, that is a HUGE generalization, but seems to be true when looking at our little people and their friends that have been identified. The best way we've found to deal with it is to treat them respectfully and with understanding.
Sorry I don't have any more solid info. If you'd like more info, I can see what I can dig up.
