Error message

• Warning: Cannot modify header information - headers already sent by (output started at /var/www/lagunaweb/includes/common.inc:2777) in drupal_send_headers() (line 1486 of /var/www/lagunaweb/includes/bootstrap.inc).
• Error: Call to undefined function mysql_connect() in eval() (line 5 of /var/www/lagunaweb/modules/php/php.module(80) : eval()'d code).