Sending text to txt.att.net through gmail works but not with mail() or phpmailer() any ideas?

Question

** Perhaps I did not make myself clear, this does not have anything to do with the use of mail() and phpmailer() like the person who tagged this question as duplicate my think...In fact it has to do with AT&T and other phone carriers inability to send email-to-sms progmatically. As stated I can send email through a mail client to a phone number @ some sms gateway just fine. The question is how do I do that using PHP and it work? **

I have been stuck on this for days....I can send a text message through gmail or my company email to [email protected] and that works fine. However when trying to send an email through php mail() or phpmailer it does not work, texts are not received. I have used the exact same code with vtext.com no problems at all on either of the php options mentioned above. Below is an example of the code I am using to send the messages:

function smtpmailer($to, $from, $from_name, $subject, $body) { 
global $error;
$mail = new PHPMailer();
$mail->IsSMTP();
$mail->SMTPDebug = 1;
$mail->SMTPAuth = true;
$mail->SMTPSecure = 'ssl'; // secure transfer enabled REQUIRED for GMail
$mail->Host = 'smtp.gmail.com';
$mail->Port = 465; 
$mail->Username = '[email protected]';  
$mail->Password = 'xxxxxxx';   
$mail->ContentType = 'text/plain';
$mail->IsHTML(false);         
$mail->SetFrom($from, $from_name);
$mail->Subject = $subject;
$mail->Body = $body;
$mail->AddAddress($to);
if(!$mail->Send()) {
    $error = 'Mail error: '.$mail->ErrorInfo; 
    return false;
} else {
    $error = 'Message sent!';
    return true;
}
}

smtpmailer('[email protected]', '[email protected]', 'Bryan', 'Good Morning!', 'This is Test 4!');

ANY help on this would be awesome, I keep seeing the same code posted over and over and over again:

mail("[email protected]", "Test7", "Test7", "From: Bryan <[email protected]>\r\n");

however this does not work at all.... Thank-You So Much!