When shooting an arrow into the bottom face of a block, the arrow will not be drawn back to the shooter when close.
To reproduce: (works creative mode and survival)
Place a block in the air
Shoot the bottom face with a fully charged bow and arrow
Try and pick the arrow up.
Confirmed on 1.4.2. However, it seems that if you are in creative mode and you fly up past the block, you will pick the arrow up, and same in survival mode if you build up, but only once your feet are at the same level as the arrow. Not sure if this is intentional, but it doesn't seem like the right behaviour.