Not spawning in same place after saving and loading later.

Put the summary of the bug you're having here: I loaded up my map and spawned in a different place than where I was when I had saved.

What I expected to happen was...:
Describe what you thought should happen here: I had expected to be in the same spot as when I saved.

What actually happened was...:
Describe what happened here: I was in a tunnel I was mining near the surface when I had saved. When I reloaded the map I was on the surface approximatley 5 levels above where the tunnel was. The tunnel was 1 block wide by 2 blocks high.

Steps to Reproduce:
1. Put a step by step guide on how to trigger the bug here: Basically mine a small enough shaft to stand in.
2. ... Save the game.
3. ... Load the game.