attached email sending in php 5.2.11

I have a problem with sending email with attachment.

It is working on server which has php 5.2.8 installed while it's not working on the other sever which has php 5.2.11 installed. Following is the function

function mail_attachment($filename, $path, $mailto, $from_mail, $from_name, $replyto, $subject, $message) 
{
    $file = $path.$filename;
    $file_size = filesize($file);
    $handle = f开发者_如何学JAVAopen($file, "r");
    $content = fread($handle, $file_size);
    fclose($handle);
    $content = chunk_split(base64_encode($content));
    $uid = md5(uniqid(time()));
    $name = basename($file);
    $header = "From: ".$from_name." <".$from_mail.">\r\n";
    $header .= "Reply-To: ".$replyto."\r\n";
    $header .= "MIME-Version: 1.0\r\n";
    $header .= "Content-Type: multipart/mixed; boundary=\"".$uid."\"\r\n\r\n";
    $header .= "This is a multi-part message in MIME format.\r\n";
    $header .= "--".$uid."\r\n";
    $header .= "Content-type:text/plain; charset=iso-8859-1\r\n";
    $header .= "Content-Transfer-Encoding: 7bit\r\n\r\n";
    $header .= $message."\r\n\r\n";
    $header .= "--".$uid."\r\n";
    $header .= "Content-Type: application/octet-stream; name=\"".$filename."\"\r\n"; // use diff. tyoes here 
    $header .= "Content-Transfer-Encoding: base64\r\n";
    $header .= "Content-Disposition: attachment; filename=\"".$filename."\"\r\n\r\n";
    $header .= $content."\r\n\r\n";
    $header .= "--".$uid."--";
    if (mail($mailto, $subject, "", $header)) {
       echo  "Picture Uploaded Successfully... OK"; // or use booleans here
  return true;
    } else {
        echo  "mail send ... ERROR!";
return false;
    }
}

Use a mail library, like Swift Mailer or PHPMailer.