title: Edit a blank invoice line in QuickBooks SDK
body: <p>I am writing a small utility to modify invoice line items in QuickBooks using the SDK.  Everything is working well until I hit a blank line in the invoice or a line that only has a description used for spacing/separating line items.  It will continue to process the request, but it will not recreate the line in the invoice, it's as if it's deleting the line.  There is nothing in the documentation that I see outside of the documented required fields that would cause this behavior.</p>
  
  <p>I am using the IORInvoiceLineMod interface implementation.  It seems that only this special case is causing the problems.</p>