Drupal theme function for menu_block not being called

I am using menu_block with D7. I read the readme (or: http://drupal.org/node/748022) but when I define a function kw_menu_item_link__menu_block__6() in my template.php, it is not being called.

Does anyone have an idea why?开发者_如何学编程

Update: clearing the cache does not solve the problem.

If it's a new template.php file, try clearing the theme cache, to force the theme system read the new file.

Update: Try using the Theme Developer module to double check that you have the function named correctly.