Back in the day of hMod, my server had two very good grief protection tools. They were GriefAlert and Blocks. The reason these tools were so great were because of their mysql logging. Basically, all grief alerts were logged to a mysql table and you could set what items to report based on a config file. Blocks basically logged all player actions, including the date, action, x,y,z co-ordinates, and player name all to a mysql table. This was great for sorting through logs to see who did what when and where. With these two mods I was able to create one of the least griefed services with a very happy player base. When ever a player griefed my server, players could take a screen shot with the x, y, z co-ordinates of where the grief tooked place and I would just look it up in the mysql table and then ban the griefer. Right now there aren't any craftbukkit mods that can do this. I'm hoping someone develops these because they were very great mods and helped my server out more than any other mod available.