Mail i feedback.php

Jeg har følgende blok i php-nuke. Programmet skulle gerne sende en mail til adminmail, men når jeg skifter adminmail ud med min egen mailadresse i programmet  modtages ingen mails via denne formular."  <?php

/************************************************************************/
/* PHP-NUKE: Web Portal System                                          */
/* ===========================                                          */
/*                                                                      */
/* Copyright (c) 2002 by Francisco Burzi (fbc@mandrakesoft.com)        */
/* http://phpnuke.org                                                  */
/*                                                                      */
/* Based on php Addon Feedback 1.0                                      */
/* Copyright (c) 2001 by Jack Kozbial                                  */
/* http://www.InternetIntl.com                                          */
/* jack@internetintl.com                                                */
/*                                                                      */
/* This program is free software. You can redistribute it and/or modify */
/* it under the terms of the GNU General Public License as published by */
/* the Free Software Foundation; either version 2 of the License.      */
/************************************************************************/

if (!eregi("modules.php", $PHP_SELF)) {
    die ("You can't access this file directly...");
}

require_once("mainfile.php");
$module_name = basename(dirname(__FILE__));
get_lang($module_name);

/**********************************/
/* Configuration                  */
/*                                */
/* You can change this:          */
/* $index = 0; (right side off)  */
/**********************************/
$index = 1;
$subject = "$sitename "._FEEDBACK."";
/**********************************/

include("header.php");

$form_block = "
    <center><font class=\"title\"><b>$sitename: "._FEEDBACKTITLE."</b></font>
    <br><br><font class=\"content\">"._FEEDBACKNOTE."</font>
    <FORM METHOD=\"post\" ACTION=\"modules.php?name=Feedback\">
    <P><strong>"._YOURNAME.":</strong><br>
    <INPUT type=\"text\" NAME=\"sender_name\" VALUE=\"$sender_name\" SIZE=30></p>
    <P><strong>"._YOUREMAIL.":</strong><br>
    <INPUT type=\"text\" NAME=\"sender_email\" VALUE=\"$sender_email\" SIZE=30></p>
    <P><strong>"._MESSAGE.":</strong><br>
    <TEXTAREA NAME=\"message\" COLS=30 ROWS=5 WRAP=virtual>$message</TEXTAREA></p>
    <INPUT type=\"hidden\" name=\"opi\" value=\"ds\">
    <P><INPUT TYPE=\"submit\" NAME=\"submit\" VALUE=\""._SEND."\"></p>
    </FORM></center>
";

OpenTable();
if ($opi != "ds") {
    echo "$form_block";
} elseif ($opi == "ds") {
    if ($sender_name == "") {
    $name_err = "<center><font class=\"option\"><b><i>"._FBENTERNAME."</i></b></font></center><br>";
    $send = "no";
    }
    if ($sender_email == "") {
    $email_err = "<center><font class=\"option\"><b><i>"._FBENTEREMAIL."</i></b></font></center><br>";
    $send = "no";
    }
    if ($message == "") {
        $message_err = "<center><font class=\"option\"><b><i>"._FBENTERMESSAGE."</i></b></font></center><br>";
    $send = "no";
    }
    if ($send != "no") {
    $msg = "$sitename\n\n";
    $msg .= ""._SENDERNAME.": $sender_name\n";
    $msg .= ""._SENDEREMAIL.": $sender_email\n";
    $msg .= ""._MESSAGE.": $message\n\n";
    $to = $adminmail;
    $mailheaders = "From: $nukeurl <> \n";
    $mailheaders .= "Reply-To: $sender_email\n\n";
    mail($to, $subject, $msg, $mailheaders);
    echo "<P><center>"._FBMAILSENT."</center></p>";
    echo "<P><center>"._FBTHANKSFORCONTACT."</center></p>";
    } elseif ($send == "no") {
    OpenTable2();
    echo "$name_err";
    echo "$email_err";
    echo "$message_err";
    CloseTable2();
    echo "<br><br>";
    echo "$form_block"; 
    }
}

CloseTable(); 
include("footer.php");

?>