[support] 404 or alias for menu hook

[Ivan Sergio Borgonovo]

In a hierarchy of menu in admin/settings/mymodule
made mainly by

MENU_NORMAL_ITEM, MENU_DEFAULT_LOCAL_TASK and MENU_LOCAL_TASK

I'd like that if anything deeper than:

admin/settings/mymodule

is rubbish it get a 404 or a redirect to admin/settings/mymodule

eg. admin/settings/mymodule/ashasha
or
admin/settings/mymodule/somefunction/jajasha
-> 404

but I get:
warning: array_merge() [function.array-merge]: Argument #1 is not an
array in /*/includes/menu.inc on line 415.
warning: Missing argument 1 for drupal_get_form()
in /*/includes/form.inc on line 49. warning:
Missing argument 1 for drupal_retrieve_form()
in /*/includes/form.inc on line 179. warning:
call_user_func_array() [function.call-user-func-array]: First
argument is expected to be a valid callback, '' was given
in /*/includes/form.inc on line 218.

hints?

-- 
Ivan Sergio Borgonovo
http://www.webthatworks.it