This is impossible to see without the use of a texture pack, so one to make this clear is attached. Due to being small, this probably isn't subject to the horrible looking mirroring effects other crosses would exhibit.

To reproduce, apply the texture pack and place down candles. Note how candle cakes as well as single candles always have the arrow pointing in one direction regardless of where the plane is viewed.

When there are multiple candles in one block, some planes are actually mirrored correctly, even though others are not.

Fixed models attached.