error thrown when doing nrepl-jack-in or nrepl

nrepl-err

Debugger entered--Lisp error: (wrong-type-argument stringp nil)
  nrepl-init-repl-buffer(#<process nrepl<5>> nil)
  nrepl(37440)
  call-interactively(nrepl record nil)
  command-execute(nrepl record)
  (progn (setq prefix-arg current-prefix-arg) (command-execute chosen-item (quote record)))
  (unwind-protect (progn (setq prefix-arg current-prefix-arg) (command-execute chosen-item (quote record))) (smex-rank chosen-item) (smex-show-key-advice chosen-item) (run-at-time 0.01 nil (lambda (cmd) (setq last-repeatable-command cmd)) chosen-item))
  (if smex-custom-action (let ((action smex-custom-action)) (setq smex-custom-action nil) (funcall action chosen-item)) (unwind-protect (progn (setq prefix-arg current-prefix-arg) (command-execute chosen-item (quote record))) (smex-rank chosen-item) (smex-show-key-advice chosen-item) (run-at-time 0.01 nil (lambda (cmd) (setq last-repeatable-command cmd)) chosen-item)))
  (let ((chosen-item (intern (smex-completing-read commands initial-input)))) (if smex-custom-action (let ((action smex-custom-action)) (setq smex-custom-action nil) (funcall action chosen-item)) (unwind-protect (progn (setq prefix-arg current-prefix-arg) (command-execute chosen-item (quote record))) (smex-rank chosen-item) (smex-show-key-advice chosen-item) (run-at-time 0.01 nil (lambda (cmd) (setq last-repeatable-command cmd)) chosen-item))))
  smex-read-and-run(("nrepl" "nrepl-jack-in" "ecb-activate" "server-start" "package-install" "package-refresh-contents" "clojure-jack-in" "ecb-show-layout-help" "ansi-term" "eshell" "shell" "ecb-toggle-enlarged-compilation-window" "speedbar" "kill-emacs" "ecb-hide-ecb-windows" "slime-connect" "ecb-deactivate" "ecb-toggle-compile-window" "ecb-show-ecb-windows" "info" "vi-mode" "load-theme" "ecb-change-layout" "browse-url" "byte-compile-file" "recover-this-file" "browse-url-firefox" "byte-recompile-file" "package-list-packages" "ielm" "slime-mode" "org-version" "clojure-mode" "ecb-customize" "make-directory" "browse-url-elinks" "comint-send-input" "open-java-project" "ecb-store-window-sizes" "auto-indent-global-mode" "byte-recompile-directory" "ecb-customize-most-important" "ansi-color-for-comint-mode-on" "package-list-packages-no-fetch" "cd" "5x5" "arp" "dbx" "dig" "erc" ...))
  (if (smex-already-running) (smex-update-and-rerun) (and smex-auto-update (smex-detect-new-commands) (smex-update)) (smex-read-and-run smex-ido-cache))
  smex()
  call-interactively(smex nil nil)