I'm reading in the game media about a nudity bug that's being patched out in the non-English versions of Skyrim and they're saying that it's not in the English version. That's not true. I have two NPCs that often appear in their underwear in my games. One is the Courier and the other is the Redguard woman who is being harrassed by the Alik'r as they search for the right woman. It doesn't really bother me; it's one of the funnier glitches but I just thought you should know if you didn't already. Funny it's called nudity bug because they aren't naked.
Pretty sure the naked courier is not a bug. Just a little something put in because it is funny. You'd want to lighten the mood up with loincloth nudity, too if you gave up on making Bosmer funny.