А так правильно?
$to = “кому”;
$subject = “тема письма”;
$text = “текст самого письма”;
$from = “от кого”;
$kodir = “кодировка письма”;
$kodir="windows-1251";
$header = "From: $from\nReply-To: $from\n";
$header .= "MIME-Version: 1.0\n";
$header .= "Content-Type: text/plain; charset=$kodir\n";
// $header .= "Content-Type: text/html; charset=$kodir\n";
$header .= "Content-Transfer-Encoding: 8bit\n\n";$header .= "$text\n";
mail($to, $subject, $text, $header);