erro em update

estou tentando editar uns campos no sql e não estou conseguindo ja refiz o script 4x e nao acho o erro, oque será?

formulario

echo "<table width=\"550\" border=\"$bd\" cellspacing=\"0\" cellpadding=\"0\">\n"; echo "<form name=\"alterar\" method=\"post\" action=\"x.alterando.noticias.php?id=$id&menu=$menu&alterar=$alterar\">\n"; echo "<tr>\n"; echo "<td colspan=\"2\" height=\"70\"></td>\n"; echo "</tr>\n"; echo "<tr>\n"; echo "<td colspan=\"2\" align=\"center\"><img src=\"imgs/alterar.gif\" width=\"220\" height=\"40\"></td>\n"; echo "</tr>\n"; echo "<tr>\n"; echo "<td colspan=\"2\" height=\"55\"></td>\n"; echo "</tr>\n"; echo "<tr>\n"; echo "<td width=\"120\" height=\"25\" class=\"texto\"> Data</td>\n"; echo "<td width=\"430\"><input name=\"xdata\" value=\"$vr[data]\" type=\"text\" maxlength=\"10\" class=\"campo2\" onkeypress=\"return txtBoxFormat(document.incluir, 'xdata', '99.99.9999', event);\"></td>\n"; echo "</tr>\n"; echo "<tr>\n"; echo "<td height=\"110\" bgcolor=\"#F2F2F2\" class=\"texto\"> Descrição</td>\n"; echo "<td bgcolor=\"#F2F2F2\"><textarea name=\"desc\" rows=\"5\" class=\"camposaltura\">$vr[desc]</textarea></td>\n"; echo "</tr>\n"; echo "<tr>\n"; echo "<td height=\"180\" class=\"texto\"> Notícia</td>\n"; echo "<td><textarea name=\"noticia\" rows=\"10\" class=\"camposaltura\">$vr[noticia]</textarea></td>\n"; echo "</tr>\n"; echo "<tr>\n"; echo "<td height=\"25\" bgcolor=\"#F2F2F2\" class=\"texto\"> Fonte</td>\n"; echo "<td bgcolor=\"#F2F2F2\"><input name=\"fonte\" value=\"$vr[fonte]\" type=\"text\" size=\"30\" class=\"campo2\"></td>\n"; echo "</tr>\n"; echo "<tr>\n"; echo "<td colspan=\"2\" height=\"50\"></td>\n"; echo "</tr>\n"; echo "<tr>\n"; echo "<td height=\"25\"></td>\n"; echo "<td><input type=\"image\" src=\"imgs/alterando.gif\" width=\"80\" height=\"18\" border=\"0\"></td>\n"; echo "</tr>\n"; if ($msg == ok) { echo "<tr>\n"; echo "<td colspan=\"2\" height=\"50\" align=\"center\" class=\"erro\">Alterado com sucesso!</td>\n"; echo "</tr>\n"; } echo "<tr>\n"; echo "<td colspan=\"2\" height=\"100\"></td>\n"; echo "</tr>\n"; echo "</form>\n"; echo "</table>\n";

alterando

<?require ('session.php');$alt = "UPDATE noticias SET data='$xdata', desc='$desc', noticia='$noticia', fonte='$fonte' WHERE id='$alterar'";$res = mysql_db_query( "estrela_estrela", $alt, $link );mysql_close($link);Header("Location: alterando.noticias.php?id=$id&menu=$menu&alterar=$alterar&msg=ok");?>

campos no MySQL

id - smallint(5) - auto_increment

data - varchar(20)

desc - text

noticia - text

fonte - varchar(50)