mail() return path

[mlschutz]

I'm trying to send emails and know that there are a good bit of bad addresses. I try to set the return path to a specific mailbox for the returned addresses but when I test it with a bad address it doesn't come back. Here's my code:

$header = "Return-Path: <[e-mail]>\n";
$header .= "Content-type: text/html; charset=us-ascii\r\nFrom: PEOPLE<[e-mail]>\r\n";
mail("[e-mail]", $mailsubject, $body, $header);

Please help!