I did that:

1. In core\columns_api.php add these strings:

   function print_column_title_reporter_id( $p_sort, $p_dir, $p_print = false ) {
   echo '<td class="center">';
   print_view_bug_sort_link( lang_get( 'reporter' ), 'reporter_id', $t_sort, $t_dir );
   print_sort_icon( $t_dir, $t_sort, 'reporter_id' );
   echo '</td>';
   }

   function print_column_reporter_id( $p_row, $p_print = false ) {
   echo '<td class="center">';
   if(1==$v_reporter_id) echo ' ';
   else echo user_get_name( $v_reporter_id );
   echo '</td>';
   }

2. In function custom_function_default_get_columns_to_view in core\custom_function_api.php add this:
   $t_columns[] = 'reporter_id';

But it works incorrect. The column named 'Reporter' is added, but it contains only 'user0' values

You're solution is OK, You simply have to modify the program as follows :

function print_column_reporter_id( $p_row, $p_print = false ) {
echo '<td class="center">';
if(1==$v_reporter_id) echo ' ';
#else echo user_get_name( $v_reporter_id );
else echo prepare_user_name( $p_row['reporter_id'] );
echo '</td>';
}

So I have upgraded Mantis in 1.0.0a2, but it don't change the problem...
Thanks Alex007, for your answer who, with a little modification, correct my problem

show note (0009943)

10x to Rudboy. It's realy works!!!

This is available with 1.2.x .