note 15184 added to function.include

If you want your php to write xml with a reference to a stylesheet, include() can cause problems with IE6. Make sure that none of your included files contain newlines at the end (after the ?> closing php tag). These get prepended to the beginning of the xml document you are trying to write. The stylesheet mechanism does not like newlines before the beginning <xml> tag. http://www.php.net/manual/en/function.include.php