In 1.2 and 1.2.3, cloning command is causing mad lag, whereas in 1.1.x it was fine. I could clone huge areas without any lag, and fill areas (around 700’000 blocks with air) too without lag either (1.5 seconds). Now I clone or fill areas around 30’000 blocks, and it takes about 2 seconds to do, and i have 16 to do in total. So it takes 32 seconds for something that used to take 1.5 seconds in 1.1.x. Please fix that issue, make fill and clone commands better and faster.