|Issue tags:||needs backport to D7|
The hook_menu() documentation describes a settings page at admin/config/foo as an example for how to implement tabs. However, if you follow this example, your page won't show up, because pages directly under admin/config don't appear on admin/config. Per https://drupal.org/node/549094#configuration, you need to put your pages under a sub-category, e.g. admin/config/development/foo.