/**
* Validate quote state to be integrated with obe page checkout process
*/
public function validate()
{
$helper = Mage::helper('checkout');
$quote = $this->getQuote();
if ($quote->getIsMultiShipping()) {
Mage::throwException($helper->__('Invalid checkout type.'));
}
if ($quote->getCheckoutMethod() == self::METHOD_GUEST && !$quote->isAllowedGuestCheckout()) {
Mage::throwException($this->_helper->__('Sorry, guest checkout is not enabled. Please try again or contact store owner.'));
}
}
