chmod after move_uploaded_file

My server using suPHP.
We had problem with uploading files. It's perrmission set to "0600".

And added following line in "includes/file.inc" after
(line #:572)
if (!move_uploaded_file($_FILES['files']['tmp_name'][$source], $file->filepath)) {
...
}
@chmod($file->filepath, 0664);
(line #:577)

It would be great if you include it drupal core.