Well, I don't remember the scene exactly, but I'm pretty sure, that this was meant rather sarcastic.
Latin is really not an easy language and has a rather complex grammar. Besides that it's not really spoken in everyday life anymore and only read from ancient texts or used in quite specialized contexts (law and medical terms, recitated prayers), but not spoken in direct dialogue. That's why it's commonly referred to as a "dead language".
So what she probably means is, that somebody who claims to speak Latin (fluently) is either an impostor or some weird genius (or works in Vatican, which doesn't make it any better ;)).