A lot of people are dubious as to wether or not this actualy works. I for one am a beleiver despite the fact that I used a crap hypnotist to help me stop smoking last year. He was convinced he had hypnotised me and wouldn't have it when I said it didn't work. An hour later I lit a cig! :?
I do beleive you may need to be susceptible to it and that the person doing it needs to be competent.