Since Ryan and Zack can't play nice, I've installed a bunch of anti-griefing mods on the server today.
I now have a mod that reports any use of flint and steal, lava, tnt etc. and puts it in a logfile. It stores the name of the person who used it and the coordinates of where it was used.
You can now report griefing with "/report Ryan and Zack get really mad all the time"
You can now lock chests and doors by left clicking them while holding sticks.
In addition to these mods, I've also added a mod that lets you look up crafting recipes in game by typing something along the lines of "/recipe diamondsword".