Bugs and lighting bugs

Put the summary of the bug you're having here first I want to tell you I will try to be the guy who reports bugs ok. Now there was a glitch when u are behind a 2 blocks high there will be a shadow glitch on the top block. 2 if you look at a rail from a distence it look weird. And cactese on the sides it is not cover up that is all.

What I expected to happen was...: I thout it was there befor the pre release but it is a bug in the pre release.
Describe what you thought should happen I thout it was there for dec but I think notch a jeb might want to change it jeb notch ask your buyers of minecraft if they want the bugs changed.

*What actually happened was...:*i saw it whal I was playing minecraft
Describe what happened herei thout to reports the bug

Steps to Reproduce:
1. Put a step by step guide on how to trigger the bug here
2. ...from about 5/4 blocks away the rails look weird.
3. ...the catace on the corners you can see throu.