my @mail_to = ($pro_box) ? ( 'person1@mycompany.com',
                                  'person2@mycompany.com', 
                                  'person3@mycompany.com', 
                                  'person4@mycompany.com') : ( 'person2@mycompany.com',
                                                               'person3@mycompany.com', 
                                                               'person4@mycompany.com');