Hya,
Recently I had to work with FTP over PHP, since I didn't found any help about this topic I decided to post this here. If you need to chmod one file, I tested this on the ftp server using a ftp client and after I knew that the ftp server supported chmod I used the following commands:
$upload = ftp_put($conn_id, "/home/to/public_html/index.php", $source_file, FTP_ASCII);
$ch=@ftp_site($conn_id,"chmod 755 /home/to/public_html/index.php");
Hope this help!
T?