Opened piston bug

Hi I'm Bali.
I've got a bug.

1. Put a piston to wall and two redstone block (2013-03-16_13.13.55)
+<-3.
/<-1. +<-2. += Redstoneblock /= Piston
2. Break the right bolck.
3. Break the left block
THE PISTON IS OPENED

Oh the 2nd bug is the generate. This world is superflat>Redstone ready and this is the generate...