Dough usage (until Doctrine 2.3's Value object support)

gistfile1.txt

    /**
     * @param MoneyInterface $defaultIncrementalFee
     */
    public function setDefaultIncrementalFee(MoneyInterface $defaultIncrementalFee)
    {
        $this->_defaultIncrementalFee = $defaultIncrementalFee;
        $this->defaultIncrementalFee = $defaultIncrementalFee->reduce()->getAmount();
    }

    /**
     * @return MoneyInterface
     */
    public function getDefaultIncrementalFee()
    {
        if (null === $this->_defaultIncrementalFee && null !== $this->defaultIncrementalFee) {
            $this->_defaultIncrementalFee = new Money($this->defaultIncrementalFee);
        }

        return $this->_defaultIncrementalFee;
    }