Steve Sailer's insight into the secure masculinity of biblical male names has been of great personal interest recently. While it's a great place to start, however, it isn't without exceptions. He never claimed it was, of course--I've just finally gotten around to putting a little pressure on it.
Aaron/Erin is the first exception that comes to mind, though I'm sure there are more. Enlighten me, please. That the feminine origins are distinct from the masculine ones doesn't negate (at least not fully) the functional consequences of onomastic homonyms when it comes to given names as far as I'm concerned.