They are grouped but the Option Name and then sorted on the Sort Order ...
If you look around line 641 in the options_values_managers.php you will find the SELECT statement:
PHP Code:
$values = "select pov.products_options_values_id, pov.products_options_values_name, pov2po.products_options_id, pov.products_options_values_sort_order from " . TABLE_PRODUCTS_OPTIONS_VALUES . " pov left join " . TABLE_PRODUCTS_OPTIONS_VALUES_TO_PRODUCTS_OPTIONS . " pov2po on pov.products_options_values_id = pov2po.products_options_values_id left join " . TABLE_PRODUCTS_OPTIONS . " po on pov2po.products_options_id = po.products_options_id where pov.language_id = '" . (int)$_SESSION['languages_id'] . "' and po.language_id = pov.language_id and pov2po.products_options_values_id !='" . PRODUCTS_OPTIONS_VALUES_TEXT_ID . "' order by po.products_options_name, LPAD(pov.products_options_values_sort_order,11,'0'), pov.products_options_values_name";