Explosion settings

There should be an explosion setting (Currently I only know mobgriefing, which completely turns it off) which limits destruction from explosions to following blocks: Sand, Gravel, all kinds of dirt, torches. No Redstone item should be affected. This way, we could still destroy a lot of terrain whenever we want, but without having to rebuild stuff we had built underneath. Also, this would be a great setting for creating explosive traps on PvP servers with protected "claim land" mods.