Need to add new customer as Qualified Lead

Using the following I can add a new customer with status as Closed-Won:

        Dim oCustomer As New Netsuite.Customer
        Dim oStatus As New Netsuite.RecordRef
        Dim oResponse As New Netsuite.WriteResponse
        ...fill in other customer info...
        oStatus.internalId = "13" 'Closed Won
        oCustomer.entityStatus = oStatus
        oResponse = oNetsuiteService.add(oCustomer)

How do I make the customer listed as a qualified lead?  I tried changing values above based on documentation and also tried adding oCustomer.Stage property but just received errors like this:

- <soapenv:Envelope xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance