これが最終的に解決した方法です (Nic Marsh からのプルリクエスト):
(defn arg-count [function]
"Counts the number of arguments the given function accepts"
(let [method (first (.getDeclaredMethods (class function)))
parameters (.getParameterTypes method)]
(alength parameters)))
(defn call-with-correct-args [function & args]
"Call the given function on all given args that it can accept"
(let [amount-accepted (arg-count function)
accepted-args (take amount-accepted args)]
(apply function accepted-args)))
(defn- conv-listener [function]
"Takes a function with one argument, which will get passed the keycode, and creates a listener"
(proxy [com.tulskiy.keymaster.common.HotKeyListener] []
(onHotKey [hotKey] (call-with-correct-args function hotKey))))
http://github.com/houshuang/keymaster-clj