NOTICE: As of CraftBukkit Build #3075, the underlying problem in both the vanilla Minecraft server and the Bukkit server has been rectified. Using ChickenJockeyFix should no longer be necessary or useful. However, if you're still using any of the earlier post-1.7.4 builds, then you'll still need the plugin.
Introduction
The implementation of the chicken jockey composite-mob in Minecraft 1.7.4 and 1.7.5 causes chickens to spawn in dark places with a baby zombie rider. The zombie will despawn but the chicken will not, and any eggs that the chicken lays can be picked up by other nearby zombies causing them to become persistent, and ignored by the hostile mob cap. Eventually, hundreds of egg-holding zombies can gather in an active area and cause unnecessary server load. This is MC-42174.
ChickenJockeyFix attempts to remedy this problem by detecting any chickens which spawn with riders, and it flags them for eventual despawn, and prevents them from laying any eggs.
Passive effects
Commands
/killeggheads
Removes all zombies who have an egg in their hands within the loaded chunks.
/killegglayers [max-height]
Removes all chickens in the loaded chunks. A maximum height can optionally be specified so that only chickens which adhere to the condition y < max-height will be removed.
