Ayuda, no se envia el mail por php.

<?
include_once "./includes/config.inc.php";
include_once $include_path . "countries.inc.php";
if($_POST[action] == "ok")
{
	if($_POST[TPL_username])
	{
		if($BPPENNYAUTOBID_TESTMODE == 'yes'){
			include "header.php";
			echo "<strong style='color: red;'>".$ERR_9999."</strong>";
			include phpa_include("template_forgotpasswd_php.html");
			include "footer.php";
			exit();
		}else{
		$sql = "SELECT email,id FROM BPPENNYAUTOBID_users WHERE nick=\"" . AddSlashes($_POST[TPL_username]) . "\" OR email='" . addslashes($_POST[TPL_username]) . "'";
		$res = mysql_query($sql);
		if($res)
		{
			if(mysql_num_rows($res) > 0)
			{
				//-- Generate a new random password and mail it to the user
				$EMAIL = mysql_result($res, 0, "email");
				$ID = mysql_result($res, 0, "id");
				$NEWPASSWD = substr(uniqid(md5(time())), 0, 6);
				$USERLANG = @mysql_result(@mysql_query("SELECT language
															FROM BPPENNYAUTOBID_userslanguage
															WHERE user=" . intval($ID)), 0, "language");
				if(empty($USERLANG)) $USERLANG = $SETTINGS['defaultlanguage'];
				include_once $include_path . "newpasswd.EN.inc.php";
				$headers = "From: " . $SETTINGS['sitename'] . " <" . $SETTINGS['adminmail'] . ">\r\n" . "Reply-To: " . $SETTINGS['adminmail'] . "\r\n" . "Return-path: " . $SETTINGS['adminmail'] . "\r\n" . "MIME-Version: 1.0\n" . "Content-Type: text/html; charset=utf-8";
				mail($to, $subject, $message, $headers);
				//-- Update database
				$query = "update BPPENNYAUTOBID_users set password='" . md5($MD5_PREFIX . $NEWPASSWD) . "'
								,reg_date=reg_date
								WHERE nick=\"" . AddSlashes($_POST["TPL_username"]) . "\"
								OR email='" . $_POST["TPL_username"] . "'";
				$res = mysql_query($query);
				if(!$res)
				{
					//print "An error occured while accessing the database: $query<BR>".mysql_error();
					exit();
				}
				include_once "header.php";
				include_once phpa_include("template_passwd_sent_php.html");
				include_once "footer.php";
				exit();
			}else
			{
				$TPL_err = 1;
				$TPL_errmsg = $ERR_100;
			}
		}else
		{
			MySQLError($query);
			exit();
		}
		}
	}else
	{
		$TPL_err = 1;
		$TPL_errmsg = $ERR_112;
	}
}
if(!$_POST[action] || ($_POST[action] && $TPL_errmsg))
{
	include_once "header.php";
	include_once phpa_include("template_forgotpasswd_php.html");
}
include_once "footer.php";
$TPL_err = 0;
$TPL_errmsg = "";
?>

Lo que hace es generar una nueva contraseña y enviar por el email ayuda.. nose cual es el error pero no me llega ningun email ni nada no pasa nada.