Mobs won't attack players?

Hello
Why won't mobs attack players? I am running 1.6.4 bukkit. Here are my plugins:
ships, ultimate arena, worldEdit, drills,simple-auto-save, mcjobs, buycraft, main(my own plugin), vault, plotme, permissionsex, multi-verse core, icontrolU, banhammer, clanwars, worldGuard, autocraft, admin chat, lottery, iconomy, endless enchant, crackshot, cfbanner, lockette, protocalLib, modifyworld, enchanter, essentialsSpawn, multiverse portals, multiverse inventories, ancasino, textplayer, ucars, essentials antibuild, autorank, chestshop, essentialschat, essentials

Please help if you can thanks in advance,
Carbuilder

 

Make sure essentials isn't blocking this with essentials protect. To check, scroll down in your essentials config to this little chunk...
Simpley scroll down to essentials protect where it says this little chunk...

enderdragon-blockdamage: true
enderman-pickup: false
villager-death: false
# Monsters won't follow players.
# permission essentials.protect.entitytarget.bypass disables this.
entitytarget: false
# Prevent the spawning of creatures.
spawn:
creeper: true
skeleton: false
Make sure entitytarget is set to false. If its true, change it, reload, and all is well.

If it is set as it should be, try adding the modifyworld.mobtarget node to your pex groups. (I suggest using groupmanager though)

If this helped you, please like my post. Thanks.