Setting a LivingEntity's walking path

Hi,

I'm trying to set the path a spider. I want to have him walk towards a location.

I've searched a bit, and found this little snippet:

Code:

    public void creatureMoveTo(LivingEntity e, Location l) {
        //Speed is 0.3F.
        ((org.bukkit.craftbukkit.v1_4_R1.entity.CraftLivingEntity)e).getHandle().getNavigation().a(l.getX(), l.getY(), l.getZ(), 0.3f);
    }

So I'm using that. But it does not seem to work: the spider simply doesn't react, the path of the spider doesn't change and the spider doesn't move any different than a spider would normally.

So I would like to know if there's any way you can actually do this...

Thanks in advance!

Alright, so I've tested this a bit with the same code: it works with a cow, but it does not work with a spider... Any idea why? Is the mob's behaviour different? Thanks!

Anyone? Thanks!

EDIT by Moderator: merged posts, please use the edit button instead of double posting.