Tony, you're positive your photos are properly tagged as portrait right? This should be in the exif - check with other programs that support the exif rotation.

If a photo is not tagged, there's no way for any device to know whether it's a portrait or landscape shot (directly out of a camera). The aspect ratios are exactly the same - remember that the image itelf is still always landscape from the camera. You'd have had to do a loss-less jpeg transformation to actually make it a real portrait oriented bitmap.