Return Receipt with Mail()

[remnant]

I'm trying to get a return receipt when the email I send has been read but it's not working. Here's what i've got:

    function emailReferral($to, $subject, $body) {
        $userInfo = $this->userInfo($_SERVER['PHP_AUTH_USER']);

    $headers  = "MIME-Version: 1.0\r\n";
    $headers .= "Content-type: text/html; charset=iso-8859-1\r\n";
    $headers .= "From: " . $userInfo['name'][0] . "<" . $userInfo['mail'][0] . "\r\n";
    $headers .= "Date: " . date("r") . "\r\n";   # fix strange time zone issue at sunmark
    $headers .= "Reply-To: " . $userInfo['name'][0] . "<" . $userInfo['mail'][0] . "\r\n";
    $headers .= "Return-Path: " . $userInfo['name'][0] . "<" . $userInfo['mail'][0] . "\r\n";
    $headers .= "Return-Receipt-To: " . $userInfo['name'][0] . "<" . $userInfo['mail'][0] . "\r\n";
    $headers .= "X-Mailer: PHP4\n"; //mailer
    $headers .= "X-Priority: 3\n"; //1 UrgentMessage, 3 Normal

    if(mail($to, $subject, $body, $headers)) {
        return true;
    }
}

The message goes through just fine, but no return receipt. Any help would be greatly appreciated.

Thanks in advance.

---

I realized that I don't think this is possible since I'm sending an e-mail to a public folder on Exchange. I still need a way to do this, so if anyone can think of something please LMK

[planetsim]

I cant see why its not working, where are you checking that the function returns true?

[remnant]

That method occurs on a submit and does return true. The email is sent with the proper headers but no return receipt is sent back to the person in the from header.

I appended on to my first post that this email is sent to a public folder in Exchange. I think that's the problem because even when I send mail to the public folder from Outlook requesting a return receipt I don't get one.

I'm going to have to come up with another method of letting the sender know their message has been received.

Thanks for the reply.