William Gibson, Idoru, chapter 16:
The characters have never met in person; they are interacting in a virtual space. Zona Rosa lives in Mexico, and is speaking (or writing) Spanish. She has actually said “chinga tu madre”, which in this context is an idiomatic expression of amazement and disgust. The machine translator that has been automatically rendering all her dialogue into English has mistakenly opted for a literal translation.
Wikipedia reminds me that:
In William Gibson's Idoru, Two of the characters meet only online, in a virtual space. At one point they are conversing. The first character says something innocuous, and the second remarks “Fuck your mother.” She is Mexican, has been speaking in Spanish the whole time, and everything we have read has been an automatic machine translation.