problemas con UPDATE

[yassir]

$cod = $_GET['cod'];
$id = $_GET['login'];
$prod = $_GET["nomprod"];
$vers = $_GET["version"];

echo "$cod</br>";
echo "$id</br>";
echo "$prod</br>";
echo "$vers</br>";


function conectarse() {

$db_host="localhost";
$db_nombre="bdsage";
$db_user="root";
$db_pass="";

mysql_connect(localhost,$db_user,$db_pass)

or die("error conectando");

mysql_select_db($db_nombre ) or die("Error seleccionando la base de datos.");

}
conectarse();


$result = mysql_query (" select * from tprodusu where login = '" . $id ."' and nomprod = '" . $prod ."' and version = '" . $vers ."' ") or die(mysql_error());
if (mysql_num_rows($result)!=0){

while($consulta = mysql_fetch_array($result)){

echo $consulta['login']." ---- ".$consulta['nomprod']." ---- ".$consulta['version']." ---- ".$consulta['fechainicio']." ---- ".$consulta['fechafin']."<br>";

echo "introduce nuevos datos del cliente.\n";
$prodanterior=$consulta[nomprod];
$versionanterior=$consulta[version];

echo "$prodanterior";
echo "$versionanterior";
?>


<form name="form1" method="post" action="modcondprod.php">
<select name="select" onchange="slctryole(this,this.form.select2)">
<option>- - Seleccionar - -</option>
<option value="contaplus">Contaplus</option>
<option value="facturaplus">Facturaplus</option>
<option value="nominaplus">Nominaplus</option>
<option value="tpvplus">Tpvplus</option>
</select>

<select name="select2">
<option>- - - - - -</option>
</select>

fechainicio<input size="10" id="fc_1243535810" type="text" READONLY name="fechaini" title="YYYY-MM-DD" >
<input type="button" value="ver" onclick="displayCalendarFor('fc_1243535810');">

fechafin<input size="10" id="fc_1243518445" type="text" READONLY name="fechafin" title="YYYY-MM-DD" >
<input type="button" value="ver" onclick="displayCalendarFor('fc_1243518445');">

<input type="hidden" name="id_cliente" id="id_cliente" value=" <?=$id ?>"
<input type="hidden" name="cod" id="cod" value=" <?=$cod ?>"
<input type="hidden" name="prodant" id="prodant" value=" <?=$prodanterior ?>"
<input type="hidden" name="versant" id="versant" value=" <?=$versionanterior ?>"

<INPUT TYPE="submit" NAME="accion" VALUE="Grabar">

</form>



gracias por tu paciencia