Hi! I went from 1.1-R4 straight to 1.2.3-R0.1 as an upgrade. Everything worked really smoothly - thanks to the Bukkit team for that! But the problem is that Nether is unusable any more. I get really heavy lag upon entering it, then it continues to work fine for a few seconds and I keep getting a huge lag again. This repeats endlessly. The lag affects all my servers players, so I guess it's not a client side issue. When the lag occurs, I get a huge frame rate drop. No errors on Bukkit console, running top command whilst in Nether shows no significant increase in CPU utilisation, load average stays on an approx. 1.49-1.52 (2 CPUs allocated). Running /mem in bukkit console shows that I still have plenty of RAM left. Can anybody please point me out to where I should start looking? I have reset the Nether, I have added more RAM(from 3Gb to 4Gb), nothing helps. This occurs only in Nether, End seems to be unaffected.