There is one thing that is absolutely useless with pistons facing upwards, pushing a redstone block : The piston cannot retract anymore... I know that's the same property as the one used for BUDs, but this situation is very problematical...
I don't know if this can be fixed, but I hope it can.
109th Duplicate of MC-108, please use the search function to see if your bug has already been submitted. Currently over 53% of tickets are being closed as duplicate.