Problem with PHP Email form and UTF-8

[Vilhjalmur Sveinsson]

Hi guys, i was hoping that one of you could be so kind to help me with my problem. The thing is i live in Iceland and we use characters like "æ ö þ ð á é í ó.." and so on and my PHP form does not display them correctly i can hardly read my customers requests that come from my web page. I am going to display my code in hope that there is some one out there that could help me solve this problem.

best regards,
Vilhjalmur.

here goes the code. For those of you that want to understand the icelandic words "Nafn = Name" "Netfang = Email" "Simi = Phone" "Skilabod = Messages"

<?php
$Nafn = $_POST['Nafn'];
$Netfang = $_POST['Netfang'];
$Simi = $_POST['Simi'];
$Skilabod = $_POST['Skilabod'];

$isl = array('á','é','ý','ú','í','ó','ö','þ','ð','æ','Á','É','Ý','Ú','Í','Ó','Ö','Þ','Ð','Æ');
$ens = array('a','e','y','u','i','o','o','th','d','ae','A','E','Y','U','I','O','O','TH','D','AE');
$skilabod = str_replace($isl,$ens,$skilabod);

$message = 'Nafn: ' . $Nafn .'
Netfang: ' . $Netfang .'
Skilabod: ' .$Skilabod .'
Simi: ' .$Simi;

$to = 'vilhjalmur@einkathjalfari.is';
$subject = 'Fyrirspurn fra einkathjalfari.is';

if (!mail($to, $subject, $message)){
    header('Location:gekk_ekki.html');
}
else {
    header('Location:gekk.html');
}

?>