Checkboxes on sudo admin page not themed correctly due to php error

Viewing the sudo admin page results in the following warning from php:

warning: Parameter 1 to theme_sudo_checkboxes() expected to be a reference, value given in /srv/www/drupal/includes/theme.inc on line 669.

This is because theme_sudo_checkboxes is being called via call_user_func_array, which only allows pass-by-reference if the caller explicitly notes the reference variables at call time. The result of the warning is that the theme function is not called, and the checkboxes do not render correctly. Removing the & from parameter 1 eliminates the warning and allows the checkboxes to be correctly themed.