Mobs do not spawn properly when using mob spawn eggs on ceilings

When you place a mob spawn egg on the ceiling of a block, it would spawn the mob 1 block higher and next to the block.

 

Steps to produce

1. grab a mob spawn egg.
2. grabs some blocks.
3. build a pole and place one block next to the pole as a roof.
4. Spawn the mobs using the spawn eggs under the blocks.