mysql_fetch_object(): supplied argument is not a valid MySQL result

[Plaza94]

Por favor, ayudadme a encontrar el error:

function football()
{
require("dbinfo.php");
$this->host = HOST;
$this->pass = PASS;
$this->user = USER;
$this->database = DB;
$this->prefix = PREFIX;
$this->db = $this->dbConnect();
// set variables from database
$sql = "select * from ".$this->prefix."variables where PoolID = 1";
$rs = $this->dbQuery($sql);
while($row = mysql_fetch_object($rs))
{
$this->admin_username = $row->admin_username;
$this->admin_email = $row->admin_email;
$this->domain = $row->domain;
$this->offset = $row->offset;
$this->display_offset = $row->display_offset;
$this->game_display_offset = $row->game_display_offset;
$this->timezone .= $row->timezone;
$this->timezone_display = $row->timezone_display;
$this->sitetitle = $row->sitetitle;
$this->copyright = $row->copyright;
$this->copyrightweb = $row->copyrightweb;
$this->showPicks = $row->showpicks;
$this->password_min_len = $row->password_min_len;
$this->bet_amount = $row->bet_amount;
$this->display_graphics = $row->display_graphics;
$this->logo_width = $row->logo_width;
$this->rssurl = $row->rssurl;
$this->showSpread = $row->showSpread;
$this->usespread = $row->spread;
$this->UseSMTP = $row->UseSMTP;
$this->SMTPHost = $row->SMTPHost;
$this->SMTPUser = $row->SMTPUser;
$this->SMTPPassWord = $row->SMTPPassWord;
}
}