The sort of thing that makes me grind my teeth

I was displeased to discover that "sex" is listed in the OED as a slangy synonym for "to have sexual intercourse." However, it is listed there as an intransitive verb. Therefore, sentences like this post title, in which the verb takes an object, are just as incorrect as I thought. The transitive verb form of "sex" means "to determine the sex of, by anatomical examination," and we can all agree that this is not necessary for Ms. Anderson as she has displayed her emphatically female anatomy for all to see.