Incisivis: Misato's line here has always interested me, because it's a lot more up-front about gender biases, in comparision to the real-life criticism of Shinji, which often has passing references to male and female anatomy but doesn't come right out and say, “He's a boy, he shouldn't act that way.”
I think there might be cultural differences at work. Since Japan is, relatively speaking, less advanced in its confrontation of gender roles, references to them would be more direct in normal conversation, while Misato's line doesn't quite sound as natural to a westerner's ears. I have noticed a similar frankness in some older western writing, so perhaps it's the result of cultural change more than cultural difference.
tv33: I don't think it's that uncommon for someone is the US to say something to the affect of “You're boy, not a girl, so act like one.” Of course, I've never heard such a thing directed at me, seeing as how I am such a manly man. :ph34r:
Incisivis: It's usually “Be a man!” or something along those lines. Ergo, the same thing, but just a little more indirect.