Lightroom automatically uploads two exact copies of the same photo from iphoto when it syncs

I am thrilled that Lightroom imports my photos from iphoto when it syncs, but recently, it has started importing two exact copies for every photo, they even have the same file name. I do have the "avoid dupicates" option checked in the import box, but that concerns photos that one is manually importing. Is there a setting somewhere that I am missing?