this is my first experimental clojure project. "lein run -m" gives me: "Exception in thread "main" java.lang.ClassNotFoundException: clojure.set, compiling:(incanter/core.clj:2018)" do you know why?

elso.clj

(ns elso.core
  (:gen-class)
	(:use (incanter core stats charts io datasets))
	(:refer-clojure))

(defn foo
  "I don't do a whole lot."
  [x]
  (println x "Hai, World!"))

(defn -main [& args]
	(view (histogram (sample-normal 1000))))

project.clj

(defproject elso "0.1.0-SNAPSHOT"
  :description "FIXME: write description"
  :url "http://example.com/FIXME"
  :license {:name "Eclipse Public License"
            :url "http://www.eclipse.org/legal/epl-v10.html"}
  :dependencies [[org.clojure/clojure "1.4.0"] [incanter "1.2.3-SNAPSHOT"]]
  :main elso.core
  )

question was discussed here: http://clojure-log.n01se.net/date/2013-02-16.html