The default.yaml is empty.

version: 0.0.9d-b71 (newest)

bukkit: 1.1-R4 (b1938) (now but even wasn´t working with 1.1-R3)

plugins: Backup, BukkitInventoryTools, Catacombs, ChestShop, Citizens, ecoCreature, EndermanPickup, ExactSpawn, HawkEye, HealthBar, Heroes, HeroicDeath, HideLogin, iConomy, Jail, Lumberjack, mcbans, milkAdmin, MonsterBox, NoAFK, NoFarm, Permissions, Questioner, Register, RemoteToolkitPlugin, Reporter, RPGOverhead, SimpleReserve, simpleWeather, SpawnBed, Spout, SpoutCoords, SuperSpawn, TheWerewolf, Towny, TownyChat, VanishNoPacket, Vault, WorldEdit, WorldGuard

I have also tried runying the plugin alone with heroes and vault. Even nothing happend.

This is already captured here: #49

So far, I'm not able to reproduce this bug myself. It's difficult to try and fix this when I can't observe the bug.

can you give me an example of the default.yml ? maybe it works

Sure thing:
https://raw.github.com/mung3r/ecoCreature/master/src/main/resources/default.yml

Place that into plugins/ecoCreature.

Yay!

thank you, now it works :)