While I was looking around the files, I found that the files contains unwanted trailing "\n". The files should end with "?>" and not "?>\n".
If we have a trailing \n, php will send a "\n" as a content, and this cause some functions such as header(), won't work properly.
Another style may be a Zend Framework style that doesn't have ending "?>".
I got a feedback about this at firstname.lastname@example.org, that we prefer
zend-framework style formatting from Curt Arnold <carnold_at_apache.org> and "Michael Gall" <michael_at_wakeless.net>.