Hi I maybe found a problem with your plugin.
For example the bones in the latest release of the plugin (0.0.9a) which are dropped can't be crafted into bonemeal. This also happens to feathers from chickens. I commented out all item drops from the config, and now when the monsters drop eg.
bones, it works - i can craft them to bonemeal.
I'm not sure what this could be caused by, but I think it might be your plugin.
Thanks

Interesting bug. Will look into it.

Fixed in this release:
http://dev.bukkit.org/server-mods/ecocreature/files/14-0-0-9b-cb-1-0-1-r1/