So I downloaded the latest 1.6.2 CraftBukkit Beta and I have been having problems when I start my brand new server up. I will log in and see the walls that are completely vertically flat they are spawning mostly after I shut down the server for the first time but it has happened when I loaded a new world, someone told me to save before I shut down and do /stop, but I know most people this isn't a problem and I may have my computer accidentally shut off and have these walls appear. I just want a solution besides the saving and maybe give me some advice or something that can show me the path to the solution!!!! I'm running Windows 8