As a semi-interesting (or altogether uninteresting) sidenote, in my copy of Life, the Universe and Everything Wowbagger does not say "You're a jerk, a complete kneebiter," to Arthur Dent but instead says "You're a jerk, a complete asshole."
The book doesn't have a publishing date, but it's the one that's got a collage of a towel, an eye, a fish, and a spaceship on the cover.
Update: Well, it seems that there are a number of changes between the American and British/Canadian versions of The Hitch Hiker Trilogy (of Five). For the most part it is just language-lightening for our gentler American audience], but there are also a couple significant changes in Mr. Adams' aside rants. Oh, and the American title uses the bastardised "hitchhiker" word, instead of the proper Queen's English "hitch hiker." Anyways, perhaps a subject worthy of deeper research. | 
