Code breaks after on clean installation

Hi,

I was installing your module. First time visiting the settings page for menu_breadcrumb I was able to make the settings, and I saved it.
After that I visited my pages to see if drupal breadcrumbs are fixed or not, but I did not see any changes. After that I tried but could not go back on the settings page:

warning: call_user_func_array() [function.call-user-func-array]: First argument is expected to be a valid callback, 'menu_breadcrumb_admin_settings_form' was given in C:\wampserver\www\d6\includes\form.inc on line 382.

Thanks