I had used the search function for my original issue using the keywords: 14w04b, furnace, item frame, and sideways. And before I edited the issue, I searched for: 14w04b, blocks, sideways, and item frame.
I can also confirm that this occurs in both singleplayer and multiplayer worlds, in any game mode, running 14w04b. The item frame will grow to fit the block it is placed on, but the map itself does not render.
Joshua Short
I had used the search function for my original issue using the keywords: 14w04b, furnace, item frame, and sideways. And before I edited the issue, I searched for: 14w04b, blocks, sideways, and item frame.