Sand/Gravel reproducting BUG

This reproducting BUG is old, it exist in Minecraft 1.3.2 do, and be not patched.

Much Admins need a patch to stop it.

It works with sticky pistons and sand/gravel on the top, and sticky pistons are powered with a fast clock, so the pistons push fast sand/gravel up and the game make a new block ower the pistons, and push old block up.

You can reproducting sand/gravel how much you want, and this must be stopped.

Link to YouTube:

http://www.youtube.com/watch?v=6Xvj8RyS6d0&feature=related