"Yes, Virginia, there is a talking donkey"
"Bremen Town Musicians" by the Grimm Brothers has a talking donkey. If Comcast hadn't broken Google for me, I might have found it earlier. The other search engines didn't turn up any results.
Click the link for the full story. I guess this saves Balaam's donkey from ignominy (Yeah, there's a pun in there, but if you've already figured it out, you don't need me to to be obvious).