He's ESTj. His denial of the Holocaust (or his questioning of it, anyway) fits with vulnerable. He's a pathological person, meaning he invokes the rescendent function. He would likely be classified under DSM-IV as "passive aggressive", which fits in well with the policies he's pursuing.
Article: "Iranian leader 'petty, cruel dictator,' school president says"
http://www.cnn.com/2007/US/09/24/us....ef=mpstoryview
However, he's more a match for Iran than its guide. Iran is wanting to make waves in the region without actually creating confrontation between itself and the dominant interests there. (among them Israel and the US) It wants to agonize the situation without antagonizing it. Ahmadinejad is a suitable purveyor of this strategy.
The real problem, however, is that nations in the region are still thinking in terms of nation-specific powers and influences. It is the drive among the peoples of the Middle East to think as "powers" that is the real source of the trouble there.