public static function findActiveByEmailAndUsername($strEmail, $strUsername=null, array $arrOptions=array())
	{
		$t = static::$strTable;
		$time = Date::floorToMinute();

		$arrColumns = array("$t.email=? AND $t.login='1' AND ($t.start='' OR $t.start<='$time') AND ($t.stop='' OR $t.stop>'" . ($time + 60) . "') AND $t.disable=''");

		if ($strUsername !== null)
		{
			$arrColumns[] = "$t.username=?";
		}

		return static::findOneBy($arrColumns, array($strEmail, $strUsername), $arrOptions);
	}