mail i php *bahhh*

<?

include 'db.php';

$first_name = $_POST['first_name'];
$last_name = $_POST['last_name'];
$email_address = $_POST['email_address'];
$username = $_POST['username'];
$info = $_POST['info'];


$first_name = stripslashes($first_name);
$last_name = stripslashes($last_name);
$email_address = stripslashes($email_address);
$username = stripslashes($username);
$info = stripslashes($info);


if((!$first_name) || (!$last_name) || (!$email_address) || (!$username)){
    echo 'You did not submit the following required information! <br />';
    if(!$first_name){
        echo "First Name is a required field. Please enter it below.<br />";
    }
    if(!$last_name){
        echo "Last Name is a required field. Please enter it below.<br />";
    }
    if(!$email_address){
        echo "Email Address is a required field. Please enter it below.<br />";
    }
    if(!$username){
        echo "Desired Username is a required field. Please enter it below.<br />";
    }
    include 'join_form.html';
    exit();
}

$sql_email_check = mysql_query("SELECT email_address FROM users WHERE email_address='$email_address'");
$sql_username_check = mysql_query("SELECT username FROM users WHERE username='$username'");

$email_check = mysql_num_rows($sql_email_check);
$username_check = mysql_num_rows($sql_username_check);

if(($email_check > 0) || ($username_check > 0)){
    echo "Please fix the following errors: <br />";
    if($email_check > 0){
        echo "<strong>Your email address has already been used by another member in our database. Please submit a different Email address!<br />";
        unset($email_address);
    }
    if($username_check > 0){
        echo "The username you have selected has already been used by another member in our database. Please choose a different Username!<br />";
        unset($username);
    }
    include 'join_form.html'; // Show the form again!
    exit();  // exit the script so that we do not create this account!
}

function makeRandomPassword() {
  $salt = "abchefghjkmnpqrstuvwxyz0123456789";
  srand((double)microtime()*1000000);
      $i = 0;
      while ($i <= 7) {
            $num = rand() % 33;
            $tmp = substr($salt, $num, 1);
            $pass = $pass . $tmp;
            $i++;
      }
      return $pass;
}

$random_password = makeRandomPassword();

$db_password = md5($random_password);

$info2 = htmlspecialchars($info);
$sql = mysql_query("INSERT INTO users (first_name, last_name, email_address, username, password, info, signup_date)
        VALUES('$first_name', '$last_name', '$email_address', '$username', '$db_password', '$info2', now())") or die (mysql_error());

if(!$sql){
    echo 'There has been an error creating your account. Please contact the webmaster.';
} else {
    $userid = mysql_insert_id();
Emailens Besked
?>
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Det du skal hjælpe mig med er at finde ud af hvor jeg skriver min SMTP udbyder og alt det der... tak!