Obsidian Generator In The End

When going into The End the obsidian pad (and three blocks above it) will regenerate everytime the user enters The End, this will provide an unlimited amount of obsidian. I have made a video on this bug here - http://www.youtube.com/watch?v=G3sIXg-AF0Q&noredirect=1

*What I expected to happen was when I renter The End, i would expect the pad to not regenerate.

*What actually happened was the pad would always regenerate, this would provide an unlimited amount of obsidian

Steps to Reproduce:
1. Enter the end
2. break the pad
3. leave the end through the portal
4. enter the end again
5. break the pad again
6. repeat from step 3