I installed leiningen and ran lein swank,
- sudo lein deps
- lein swank
Aquamacs has everything about SLIME, so it's OK.
Solution to this problem
David helped me to be out of trouble. As Aquamacs has built-in SLIME, I didn't need anything complex about the setup. I just needed one line - (slime-setup '(slime-repl)).
I had the same problem if I used (slime-setup '(slime-fancy)). Changing it to (slime-setup '(slime-repl)) fixed it.
I found this the easiest setup for the latest version of everything. Here's a quick summary where I"m assuming you have leiningen installed.
Install the swank-clojure plugin
Create your clojure project
Then open one of the clojure files from your project in emacs and run clojure-jack-in
You are now in a slime buffer with clojure and the dependencies for your project loaded.
I found that I needed this in my .emacs to get it to work: