That's because the literal translation of "seme" and "uke" are "attack" and "receive", but the words are still very clearly meaning "dominant" and "submissive" in a gay relationship.
I think it's safe to go by
@Allanon definition, as he seems to have a better grasp at the cultural implications of those words (that's "tsundere" kind of stuff, it's not meant to be literal).
If anything, translating it with "top" and "bottom" was probably more faithful to the intended idea, while translating it with "attack" and "accept" was basically a bad google translation.
I've checked it in 3 differents languages to be sure, and every translator went with something similar, it's not exclusive to the english dub.
EDIT: Late and gay, but still added my 2 cents, so maybe just half-gay (now, we need to wonder what half-gay could mean, that won't be an easy one).