Create a PAID invoice in Xero (Attempt #1)

NewInvoice.xml

<?xml version="1.0"?>
<Invoices>
  <Invoice>
    <Type>ACCREC</Type>
    <Contact>
      <ContactID>427f9f6c-8d02-403b-9e8b-e22a77a33c05</ContactID>
    </Contact>
    <InvoiceNumber>11001691</InvoiceNumber>
    <DueDate>2011-10-30</DueDate>
    <Date>2011-10-24</Date>
    <Status>PAID</Status>
    <AmountDue>0</AmountDue>
    <TaxType>OUTPUT</TaxType>
    <LineItems>
      <LineItem>
        <Description>Reconfigure email client on Mac and iPhone</Description>
        <Quantity>0.5</Quantity>
        <UnitAmount>165.00</UnitAmount>
        <AccountCode>42100</AccountCode>
      </LineItem>
    </LineItems>
  </Invoice>
</Invoices>