Mail Function Help Needed

[redtagus]

I have written a small script using the mail function. It works but not to all email addresses entered from a form. I suspect that SPAM silters along the way are blocking it.

Does anybody have an idea on how to improve the headers to that the mail will be delivered 100% of the time? Here is my code.

 	  $recipient = $_POST[email].", [e-mail]";
	  $subject = "Subject Text";
	  $mailheaders = "MIME-Version: 1.0\r\n";
	  $mailheaders .= "Content-type: text/plain; charset=iso-8859-1\r\n";
	  $mailheaders .= "X-Priority: 1\r\n";
	  $mailheaders .= "X-MSMail-Priority: High\r\n";
	  $mailheaders .= "X-Mailer: php\r\n";
	  $mailheaders .= "From: [e-mail]\r\n";
	  $mailheaders .= "Reply-to: [e-mail]\r\n";
	  $mailheaders .= "Return-path: [e-mail]";
	  $msg = "Thank you blah, blah, blah.\n";
	  mail($recipient, $subject, $msg, $mailheaders);