yeah, i'm through that, too. when i started coding, i often got mad about my code ('why the f... doesn't this f...ing piece of s... work?!') but the one evening one of my colleagues made a 'statement' before he left the office, i do not remember his words exactly. but it made me realize that this is not the way to go (for me, TIMTOWTDI).

Is he like this when he's not coding too?

yes, he is. he very easily gets this aggressive tone in his voice in normal discussions. i do not bother about this too much, that's the way he is and i am the way i am. (as long as i don't have to have the discussions with him i tend to avoid them (i.e. the topic PHP vs. perl, where i told him i'd love to talk about it but that i only do it as long there as well-founded argumentation).