function returnChametz() {
        if( now <= passoverEndTime ) throw; 
        if( buyerNumDeals[msg.sender] == 0 ) throw; 
        uint payment = buyerNumDeals[msg.sender] * (downPayment + buyerBonus);
        buyerNumDeals[msg.sender] = 0;
        if( ! msg.sender.send( payment ) ) throw;
        
        ReturnChametz( msg.sender, payment, now );
    }