e-mail in html

[mariox]

$query = "INSERT INTO sentcards ( cardid, toname, toemail, message, fromname, fromemail ) values( '$cardtosend', '$friendsname', '$friendsemail', '$messagetofriend', '$sendername', '$senderemail' )";
mysql_query( $query, $link );
$refs = mysql_insert_id();
$collecturl = "$siteurl/viewcard.php?id=$refs";
$subject = "oggetto";
$msg = "testo che dovrebbe essere letto in html...";

   
$headers = "From: [email]info@example.com[/email] \r\n";
$headers.= "Content-Type: text/html; charset=ISO-8859-1 ";
$headers .= "MIME-Version: 1.0 ";


mail("$friendsemail", "$subject", "$msg", "$headers");