When using an Overworld portal to go to the Nether the player does not spawn inside the Nether side portal. 

What I expected to happen was...:
I would go to the Nether an spawn in the portal

What actually happened was...:
I spawned at the Y coordinate for the Overworld portal and not the Nether side portal resulting in me dropping several blocks onto the top of the portal frame. For another portal I spawned inside the Netherrack several blocks diagonally from my portal.

Steps to Reproduce:
1. Have a portal in both the Overworld and Nether
2. Enter the portal from the Overworld