Watching the related videos, I've learned that this patch is available for all 5 third generation games in English, and most tweak the game mechanics so that all the pokemon are female. None mention how they resolved pokemon breeding in light of that.
That would be "Hyakugojuuichi." It's Japanese for 151. Internet superstar Neil Cicierega once speculated that this number represented the proof of the rum the singer was drunk on.