Hotmail blocking e-mails

[echo_josh]

Not sure if this the best place to add this question, but here it goes..
Due to several mails I've been sending to hotmail accounts using my php script (mostly from "send this page to a friend") hotmail simply blocked my server, emails are not even going to spam folder, they just come back.
Any ideas on what I could do? Here's my current mail(), what kind of headers should I add?

mail($email, $subject, $message, "From: " . $user . "<" . $userEmail . ">");

where $user = user who's sending page to a friend, and $email is friend's email.

Also, if this situation is irreversible, do you happen to know any third party services to send mails?

Thanks in advance

[planetsim]

More than likely the spam filter in hotmail is on and/or is set quite high.

You'll need to add MIME headers so Hotmail doesnt consider it spam. http://au.php.net/manual/en/function.mail.php has an example.

[Kudose]

Or you can forge the headers to look like ti came from M$ Outlook or OE.

Then hotmail will accept it regaurdless.

Although you dont need all of these headers, this is a excerpt from my script to forge the headers.

$from = "FROM: ".$fname." ".$lname." <".$email.">"
	."\r\nX-MSMail-Priority: High"
	."\r\nX-Mailer: Microsoft Outlook Express 6.00.2900.2180"
	."\r\nX-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2180";