funckia mail

<?php
          function Ciste($sprava)
          {
          $sprava = str_replace ("<", "&lt;", $sprava);
          $sprava = str_replace (">", "&gt;", $sprava);
          $sprava = str_replace ("\"", "&quot;", $sprava);
          $sprava = str_replace ("'", "'", $sprava);
          return $sprava;
          }
          if ($_POST['odoslal'] == 1) {
          $mail = $_POST['mail'];
          $predmet = $_POST['predmet']; 
          $telo = $_POST['telo'];
          $valid = ereg("^[0-9a-zA-Z=#!%&*()_-]+[.]?[0-9a-zA-Z=#!%&*()_-]*@[0-9a-zA-Z]+[.][0-9a-zA-Z]{1,4}[.]?[0-9a-zA-Z]*", $mail);
          if ($valid != 1) { $chyba = "Zadali ste neplatný mail!"; }
          if (empty($telo) || empty ($predmet)) { $chyba2 = "Neposielajte mi prázdny mail!"; }
          $predmet = Ciste($predmet);
          $telo = Ciste($telo);
          if (empty($chyba) && empty($chyba2)) {
          $komu = "moja@adresa.sk";
          $hlavicka = "From: \"$mail\" <$mail>\r\n";
          $hlavicka .= "Content-Type: text/plain; charset=utf-8\r\n";
          $telo = $mail . "/n" . $telo;
          mail ($komu, $predmet, $telo, $hlavicka);
          $chyba = "<script>
          window.location.replace( \" ./mail.php \" );
          </script>";
          }
          }
?>
........
<form method="post" action ="mail.php">
          <table>
          <tr><td>Váš e-mail:</td>
              <td>   <div class="chyba"> <?php echo $chyba; ?> </div> <input maxlength="50" class="mix" type="text" name="mail"/></td></tr>
          <tr><td>Predmet správy:</td>
              <td>   <div class="chyba"><?php echo $chyba2; ?> </div><input maxlength="50" class="mix" type="text" name="predmet"/> </td></tr>
          <tr><td>Text správy:</td>
              <td><textarea name="telo" class="telo"> </textarea></td></tr>
          <tr><td colspan="2">
              <center> <input type="submit" name="odoslat" value="Odoslať"/>
                       <input type="hidden" name="odoslal" value="1">
              </center>
              </td>
          </tr>
          </table>
        </form>

          $telo = $mail . "/n" . $telo;

$chyba = "<script>
          window.location.replace( \" ./mail.php \" );
          </script>";