public function SetAddressAsBillingAddress($sAddressId)
    {
        $oNewBillingAdr = null;
        if (0 != strcmp($this->fieldDefaultBillingAddressId, $sAddressId)) {
            $oAdr = TdbDataExtranetUserAddress::GetNewInstance();
            if ($oAdr->LoadFromFields(
                array('id' => $sAddressId, 'data_extranet_user_id' => $this->id, 'is_dhl_packstation' => '0')
            )
            ) {
                $this->SaveFieldsFast(array('default_billing_address_id' => $sAddressId));
                $oNewBillingAdr = $this->GetBillingAddress(true);
            }
        } else {
            $oNewBillingAdr = $this->GetBillingAddress();
        }

        return $oNewBillingAdr;
    }