Fatal error

[Prozinful]

Estou instalando um open source, no install, passo do 1 passo, no segundo passo apareçe isso:

Fatal error: Class 'sql_db' not found in /home/vhosts/testjogos.coolpage.biz/install.php on line 5

preciso de ajuda, não vejo o porque

<?php
if(file_exists("conexion.php"))
{
    include('conexion.php');
    $db = new sql_db;
     $regquery = "SELECT *
      FROM usuarios
      WHERE user_id = '1'";
    @ $db->sql_query($regquery);
    @ $srchuser = $db->sql_fetchrow($db->sql_query($regquery));
    if($srchuser['user_id']>0)
    {
    echo $error."<br>Bfe esta instalado...<br> Porfavor borre el archivo install.php de la carpeta de bfe.<br>Puede entrar con el usuario: Admin Password: 123456";
    }
    else
    {
    if(isset($_POST['install']))
    {
    $DescriptorFichero = fopen("SQL/SQL.txt","r"); 
    while(!feof($DescriptorFichero)){ 
        $buffer = fgets($DescriptorFichero,4096); 
        $stok .= $buffer;
    } 
    $consulteitor = explode( ';', $stok);
    while(list($var, $val) = each($consulteitor))
    {
        $n++;
        $db->sql_query($val);
        if (eregi ("#\n# (.*)#", $line, $out)) 
                  {
                      $error .= $out[1]."<br>";
                  }
    }
    $error .= $n." consultas realizadas.";
    
    echo $error."<br>Bfe esta instalado...<br> Porfavor borre el archivo install.php de la carpeta de bfe.";
    }
    else
    {
    ?>
    <form action="" method="post"><table width="657" border="1" align="center" cellpadding="0" cellspacing="0" bgcolor="#CCCCCC">
  <tr>
    <td height="21" colspan="3" valign="top"><div align="center">Battle for Embolia - Install - Paso 2 </div></td>
  </tr>
  <tr>
    <td width="77" height="14"></td>
    <td width="486"></td>
    <td width="86"></td>
  </tr>
  <tr>
    <td height="127"></td>
    <td valign="top"><table width="100%" border="1" cellpadding="0" cellspacing="0">
        <!--DWLayoutTable-->
        <tr>
          <td width="482" height="23">&nbsp;</td>
        </tr>
        <tr>
          <td height="61" align="center" valign="middle"><input type="submit" name="install" value="Data Install"></td>
          </tr>
        <tr>
          <td height="36">&nbsp;</td>
        </tr>
        </table></td>
    <td></td>
  </tr>
  <tr>
    <td height="18"></td>
    <td></td>
    <td></td>
  </tr>
  <tr>
    <td height="75"></td>
    <td align="center" valign="middle"><span class="Estilo1"><? echo $error ?></span></td>
    <td></td>
  </tr>
</table>
</form>
<?
}}
}
else
{
if(isset($_POST['install']))
{
$host = $_POST['host'];
$user = $_POST['user'];
$password = $_POST['pass'];
$db = $_POST['db'];
$error = 0;
$archivo = 'conexion.php';
$dbd = mysql_connect($host, $user, $password);
        if (!$dbd) {
          $error = 1;
          $error = "Falla en la conexion a la base de datos: ". mysql_error();
        }
$db_selected = mysql_select_db($db, $dbd);
        if (!$db_selected) {
              $error = 1;
             $error = 'Falla en la conexion a la base de datos : ' . mysql_error();
        }    
        if($error==0)    
        {

$fp = fopen($archivo, "a");
$string .= '<?php class sql_db
{
    var $num_queries;
    function sql_db()
    {
        $host = "'.$host.'";
        $user = "'.$user.'";
        $password = "'.$password.'";
        $db = "'.$db.'";
        $dbd = mysql_connect($host, $user, $password);
        if (!$dbd) {
           die("Conexion a mysql a fallado : " . mysql_error());
        }
        $db_selected = mysql_select_db($db, $dbd);
        if (!$db_selected) {
           die ("Falla en la conexion a la base de datos : " . mysql_error());
        }
    } ';
    
$string .= '    
    function sql_query($query)
    {
       $this->num_queries++;
       return mysql_query($query);
    }
    function sql_fetchrow($row)
    {
        return mysql_fetch_array($row);
    }
}?>';
$write = fputs($fp, $string);
fclose($fp);  
header('Location: install.php');
        }
}        
else
{
    $host = "localhost";
    $user = "root";
    $password = "";
    $db = "bfe";
}

?>

<form action="" method="post"><table width="657" border="1" align="center" cellpadding="0" cellspacing="0" bgcolor="#CCCCCC">
  <!--DWLayoutTable-->
  <tr>
    <td height="21" colspan="3" valign="top"><div align="center">Battle for Embolia - Install - Paso 1 </div></td>
  </tr>
  <tr>
    <td width="77" height="14"></td>
    <td width="486"></td>
    <td width="86"></td>
  </tr>
  <tr>
    <td height="127"></td>
    <td valign="top"><table width="100%" border="1" cellpadding="0" cellspacing="0">
        <!--DWLayoutTable-->
        <tr>
          <td width="232" height="19" valign="top"><div align="center">DataBase Host: </div></td>
        <td width="258" valign="top"><input name="host" type="text" value="<? echo $host ?>"></td>
        </tr>
        <tr>
          <td height="19" valign="top"><div align="center">DataBase User:</div></td>
          <td valign="top"><input name="user" type="text" value="<? echo $user ?>"></td>
        </tr>
        <tr>
          <td height="19" valign="top"><div align="center">DataBase Password:</div></td>
          <td valign="top"><input name="pass" type="text" value=""></td>
        </tr>
        <tr>
          <td height="19" valign="top"><div align="center">DataBase Name: </div></td>
          <td valign="top"><input name="db" type="text" value="<? echo $db ?>"></td>
        </tr>
        <tr align="center" valign="middle">
          <td height="27" colspan="2"><input type="submit" name="install" value="Install"></td>
          </tr>
        </table></td>
    <td></td>
  </tr>
  <tr>
    <td height="18"></td>
    <td></td>
    <td></td>
  </tr>
  <tr>
    <td height="75"></td>
    <td align="center" valign="middle"><span class="Estilo1"><? echo $error ?></span></td>
    <td></td>
  </tr>
</table>
</form>
<?  } ?>

[david.lyonnais]

Qual é o arquivo que esta a classe sql_db??? se puder coloca o script desse arquivo