If I use
/* To send HTML mail, you can set the Content-type header. */
$headers = "MIME-Version: 1.0\r\n";
$headers .= "Content-type: text/html; charset=iso-8859-1\r\n";

/* additional headers */
$headers .= "From: Birthday Reminder <birthday@example.com>\r\n";

$headers .= "Cc: [email]birthdayarchive@example.com[/email]\r\n";
$headers .= "Bcc: [email]birthdaycheck@example.com[/email]\r\n";

(example from the php.net site) there are problems with some mail servers (example home.nl and gmx.net and probably more) that there are empty linus between the header and therefor mail programs see Conten-type and everything after that as part of the body.

Just removing the \r will fix this problem; so maybe it's an idea to remove this from the example??

(I don't know whether it also works on windows os)
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Manual Page -- [url]http://www.php.net/manual/en/function.mail.php[/url]
Edit Note -- [url]http://master.php.net/manage/user-notes.php?action=edit+33666[/url]
Delete Note -- [url]http://master.php.net/manage/user-notes.php?action=delete+33666&report=yes[/url]
Reject Note -- [url]http://master.php.net/manage/user-notes.php?action=reject+33666&report=yes[/url]