The output of a customer/... request has a set of charges within an invoice. The description for each charge is blank even when an item has a name; is this the expected behaviour or should the description be the same as the corresponding item name from the subscription?

      <invoice id="ab8fad6c-e6ab-11df-8728-40407c9117fd">
        <number>2658</number>
        <type>subscription</type>
        <vatRate/>
        <billingDatetime>2010-12-02T06:04:10+00:00</billingDatetime>
        <paidTransactionId/>
        <createdDatetime>2010-11-02T18:04:43+00:00</createdDatetime>
        <charges>
          <charge id="" code="PAID_RECURRING">
            <type>recurring</type>
            <quantity>1</quantity>
            <eachAmount>19.00</eachAmount>
            <description/>
            <createdDatetime>2010-12-02T06:04:10+00:00</createdDatetime>
          </charge>
          <charge id="" code="PROJECTS">
            <type>item</type>
            <quantity>0</quantity>
            <eachAmount>4.00</eachAmount>
            <description/>
            <createdDatetime/>
          </charge>
          <charge id="" code="USERS">
            <type>item</type>
            <quantity>3</quantity>
            <eachAmount>2.50</eachAmount>
            <description/>
            <createdDatetime/>
          </charge>
        </charges>
      </invoice>