I am looking for a mod or something which would allow me to keep some chunks loaded on the SMP server I administrate.
In fact, it is a redstone circuit including a clock under a huge mob trap which triggers some pistons and water bringing loots regularly to a point. This would allow mobs to spawn continuously and the redstone circuit also to run without having to be reset when we want it to work (because the power freezes when the chunks are unloaded and doesn't restart afterwards).
Does something like that exist ?