Bukkit

• Added an item to change leaderboard's accuracy (ticks instead of seconds).
  
• Improved special sign detection when playing.
  
• Added "/cp messages" command to disable checkpoint validation messages.
  
• Changed "enable metrics" to "enable data collection" in configuration.yml in anticipation of future updates. See this page for detailed information about data collection.
  
• Improved some messages.
  

If you find a problem, be sure to report it!