When a small dripleaf's lower block is in water, and someone right-clicks with a water bucket on the lower block (to remove the water), the client gets kicked with "Packet processing error"

This only happens in multiplayer.

Steps to reproduce:

1. Place a small dripleaf plant so that its fully enclosed in water.
2. Use an empty water bucket on the top block.
3. Observe the correct behavior.
4. Right click on the lower block.