I see a lot of these in my dblog;
Warning: Cannot modify header information - headers already sent by (output started at /var/www/html/includes/bootstrap.inc:1368) in drupal_send_headers() (line 1220 of /var/www/html/includes/bootstrap.inc).
or
Warning: Cannot modify header information - headers already sent by (output started at /var/www/html/includes/common.inc:2700) in drupal_send_headers() (line 1220 of /var/www/html/includes/bootstrap.inc).
and
Warning: ini_set(): Cannot change zlib.output_compression - headers already sent in drupal_serve_page_from_cache() (line 1357 of /var/www/html/includes/bootstrap.inc).
This happens after a page not found error of a comment that had been deleted. Even though this does not generate any problem, having them filling up my dblog annoys me. Any help will be appreciated.
Thank you
Edit: Fixed it temporarily by adding a redirect.