try this..
$to = 'receiver@mail.com';
$subject = 'new mail';
$message = 'your body message';
$message = chunk_split(base64_encode($message));
$mime = "
From: your@mailaddress.com \n
Content-Type: text/html \n
Content-Transfer-Encoding: base64\n\n
$message\n";
mail($to,$subject,'',$mime);