clojure binding and resolve

gistfile1.txt

user> (binding [*ns* nil] (ns-resolve 'clojure.core '=))
#'clojure.core/=                                                                   
user> (binding [*ns* nil] (resolve 'clojure.core/=))
No message.
  [Thrown class java.lang.NullPointerException]

Restarts:
 0: [QUIT] Quit to the SLIME top level

Backtrace:
  0: java.util.concurrent.ConcurrentHashMap.get(ConcurrentHashMap.java:796)
  1: clojure.lang.Namespace.find(Namespace.java:188)
  2: clojure.core$find_ns.invoke(core.clj:3657)
  3: clojure.core$the_ns.invoke(core.clj:3689)
  4: clojure.core$ns_resolve.invoke(core.clj:3879)
  5: clojure.core$ns_resolve.invoke(core.clj:3876)
  6: clojure.core$resolve.invoke(core.clj:3885)
  7: user$eval1655.invoke(NO_SOURCE_FILE:1)
  8: clojure.lang.Compiler.eval(Compiler.java:6465)
  9: clojure.lang.Compiler.eval(Compiler.java:6431)
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