Anvil Rendering Glitched in Item Frame When Viewed from Below

Anvils in item frames render incorrectly (as if it were deeper into frame) when viewed from below. From the side or above they appear correctly.

Recreate: place item frame, place anvil in frame, view from below.

Expected result: the black/grey of the anvil should not be interrupted by the frame's brown background (as side view).

Actual: frame background seems to be in front of parts of the anvil.

Another case of this: http://www.minecraftforum.net/topic/1533766-fence-texturing-broken/#entry18750733