/**
 * Remove nofollow From Comments
 * http://toscho.de/2009/no-no-no-nofollow/
 *
 **/
function myfunction_dofollow($str) {
	$str = preg_replace(
		'~<a ([^>]*)\s*(["|\']{1}\w*)\s*nofollow([^>]*)>~U',
		'<a ${1}${2}${3}>', $str);
	return str_replace(array(' rel=""', " rel=''"), '', $str);
}
remove_filter('pre_comment_content',     'wp_rel_nofollow');
add_filter   ('get_comment_author_link', 'myfunction_dofollow');
add_filter   ('post_comments_link',      'myfunction_dofollow');
add_filter   ('comment_reply_link',      'myfunction_dofollow');
add_filter   ('comment_text',            'myfunction_dofollow');

http://toscho.de/2009/no-no-no-nofollow/

Wordpress: Remove nofollow From Comments

wordpress

PHP