Macro returning fn objects with closures

gistfile1.clj

;;; case 1

(defn get-map-of-fn [x] (fn [] x))
;= #'user/get-map-of-fn

(defmacro map-of-fn [arg] (get-map-of-fn arg ))
;= #'user/map-of-fn

(map-of-fn 1)
;= #<user$get_map_of_fn$fn__9648 user$get_map_of_fn$fn__9648@47020d4>

((map-of-fn 1))
;= IllegalArgumentException No matching ctor found for class user$get_map_of_fn$fn__9648  clojure.lang.Reflector.invokeConstructor (Reflector.java:163)

;;; case 2

(defn get-map-of-fn [x] {:f (fn [] x)})
;= #'user/get-map-of-fn
(defmacro map-of-fn [arg] (get-map-of-fn arg ))
;= #'user/map-of-fn

(map-of-fn 1)
;= IllegalArgumentException No matching ctor found for class user$get_map_of_fn$fn__10283  clojure.lang.Reflector.invokeConstructor (Reflector.java:163)

Somewhat related:

http://stackoverflow.com/questions/11191992/functions-with-closures-and-eval-in-clojure

https://gist.github.com/hiredman/921874

https://groups.google.com/forum/#!topic/clojure-dev/9JB-vKjvbhE

;;; For case 2

(macroexpand-1 '(map-of-fn 1))
;= {:f #<user$get_map_of_fn$fn__10283 user$get_map_of_fn$fn__10283@7321803a>}