form vil ikke kalde function

hejsa jeg har et poll script i filen poll.php
mit problem ligger i jeg ikke kan få min poll form til at kalde functionen CastVote, har siddet i et par timer med denne hovedepine nu, håber der er nogen der kan se mit problem og afhjælpe det, her følger lidt kode:

<-- poll.php -->
    $cookieprefix = "a_poll";
    $redirectto = "index.php";

    function HaveVoted($pid) {
        global $cookieprefix;
        if(($_COOKIE[$cookieprefix."vote".$pid]) AND ($_COOKIE[$cookieprefix."poll".$pid] == $pid)) {
            return true;
        }
        else {
            return false;
        }
    }

    function CastVote($pid, $vote) {
        global $dbtable_pollvotes; global $cookieprefix; global $redirectto;
        if(HaveVoted($pid) != true) {   
            $addvote = mysql_query("insert into pollvotes (pollid, vote) values ('$pid','$vote')");
            setcookie($cookieprefix."vote".$pid, $vote, time()+999999999);
            setcookie($cookieprefix."poll".$pid, $pid, time()+999999999);   
            header("location: $redirectto");
        }
    }

    function ShowPoll($pid) {
        global $dbtable_polls;
        $query = mysql_query("select * from polls where id='$pid'");
        if(mysql_num_rows($query) > 0)
        {
            $q = stripslashes(mysql_result($query, 0, "question"));
            $num = mysql_result($query, 0, "numofanswers");
            $kode .= "<P align=center><FONT face=\"Verdana, Arial, Helvetica, sans-serif\" size=1>".$q."</p>";
            $kode .= "<form action=\"poll.php\" method=\"post\">";
            $i = 1;
            $kode .= "<TABLE borderColor=#2a0000 cellSpacing=0 cellPadding=0 width=150 bgColor=#ece9d8 border=1><tbody>";
            while($i != $num+1) {
                $a = stripslashes(mysql_result($query, 0, "answer".$i));
                $kode .= "<TR><TD borderColor=#ece9d8 width=25><INPUT type=radio name=\"vid\" value=\"$i\"></TD><TD borderColor=#ece9d8><FONT face=\"Verdana, Arial, Helvetica, sans-serif\" size=1>".$a."</FONT></TD></TR>";
                $i++;
            }
            $kode .= "<input type=\"hidden\" name=\"pid\" value=\"$pid\" />";
            $kode .= "</table>";
            $kode .= "<br /><INPUT type=image height=14 width=50 src=\"images/knap-stem.gif\" name=\"do_vote\" value=\"submit\">";
            $kode .= "</form>";
        }
        return $kode;       
    }
    function ShowResults($pid) {
        global $dbtable_polls;    global $dbtable_pollvotes;
        $query = mysql_query("select * from polls where id='$pid'");
        $q = stripslashes(mysql_result($query, 0, "question"));
        $num = mysql_result($query, 0, "numofanswers");
        $kode .= "<div class=\"poll\">$q</div><br /><br />";
        $votesquery = mysql_query("select count(id) from pollvotes where pollid='$pid'");
        $totalvotes = mysql_result($votesquery, 0, 0);
        $i = 1;
        $kode .= "<table style=\"width: 90%; border: 1px solid black;\">";
        while($i != $num+1) {
            $a = stripslashes(mysql_result($query, 0, "answer".$i));
            $resultquery = mysql_query("select count(id) from pollvotes where pollid='$pid' and vote='$i'");
            $votes = mysql_result($resultquery, 0, 0);
            if($votes > 0) {
                $average = round(100 * $votes / $totalvotes, 2);
            } else {
                $average = "0";
            }
            $kode .= "<tr>";
            $kode .= "<td colspan=\"2\"><div>$a:</div></td>";   
            $kode .= "</tr><tr>";       
            $kode .= "<td style=\"width: 100%;\"><span style=\"width: $average%; background-color: #A0BBD0; border: 1px solid black\"></td>";
            $kode .= "<td></span>  <span style=\"text-align: right; font-weight: bold;\">$average%</span></td>";
            $kode .= "</tr>";           
            $i++;
        }
        $kode .= "</table>";
        $kode .= "<br /><div class=poll>Stemmer i alt:<br /><b>$totalvotes</b></div>";
        return $kode;
    }
<-- poll.php SLUT -->

<-- index.php -->

    $pid = 1;
    if($_POST[do_vote] and $_POST[pid] and $_POST[vid]) {
        CastVote($_POST[pid], $_POST[vid]);
    }

    if(HaveVoted($pid) == true) {
        echo ShowResults($pid);
    }
    else {
        echo ShowPoll($pid);
    }
<-- index.php SLUT -->

problemet er altså at functionen CastVote slet ikke kaldes, og jeg kan ikke umiddelbart se fejlen