I have created a taxonomy using MB Custom Post Type, however, when I paste the code into functions.php, it gives the following error in place of the taxonomy meta-box:
Warning: call_user_func() expects parameter 1 to be a valid callback, no array or string given in /home/.../wp-admin/includes/template.php on line 1050
The code generated by MB Custom Post Type is: http://txt.do/d61bi