I am working on Integration of Quickbooks Enterprise 11.0 with asp.net website using Webconnector. In Quickboks I created two custom fields in header (Customer Additional Info). I want to set...

I am working on Integration of Quickbooks Enterprise 11.0 with asp.net website using Webconnector. In Quickboks I created two custom fields named "Special Color" and "Standing Instruction" Customer Additional Info and also customize invoice using these fields in invoice's header section. I want to set values to my custom fields using QBXML from asp.net to Quickbooks.

I also created one custom field "Package Size" in Item Additional Info and also set to Invoice's Column section. It's Integration is working fine.

I am not able to set. My XML is as below

<?xml version="1.0" ?>
<?qbxml version="11.0"?>
<QBXML>
  <QBXMLMsgsRq onError="stopOnError">
    <InvoiceAddRq>
      <InvoiceAdd>
        <CustomerRef>
          <FullName>Auto Generated Customer</FullName>
        </CustomerRef>
        <TxnDate>2013-01-23</TxnDate>
        <RefNumber>0</RefNumber>
        <PONumber>PO Number</PONumber>
        <InvoiceLineAdd>
          <ItemRef>
            <FullName>Auto Generated Item</FullName>
          </ItemRef>
          <Desc >Auto Generated Invoice Item Description</Desc>
          <Quantity>1</Quantity>
          <Amount>100.00</Amount>
          <DataExt>
            <OwnerID>0</OwnerID>
            <DataExtName>Package Size</DataExtName>
            <DataExtValue>22 inch</DataExtValue>
          </DataExt>
        </InvoiceLineAdd>
      </InvoiceAdd>
    </InvoiceAddRq>
  </QBXMLMsgsRq>
</QBXML>