XML Creation

I want to create XML request for soap webservice something like below
<soapenv:Envelope xmlns:soapenv=“http://schemas.xmlsoap.org/soap/envelope/” xmlns:urn=“urn:schemas-iwaysoftware-com:iwse” xmlns:urn1=“urn:iwaysoftware:ibse:jul2003:EPQWebService_T1”>
soapenv:Body
urn1:METHOD1

</urn1:METHOD1>
</soapenv:Body>
</soapenv:Envelope>

i have written code

dim xmldoc as XmlDocument
dim root as XmlNode
dim firstnode as XmlNode
dim secondnode as XMLNode
xmldoc = new XmlDocument

root =xmldoc.AppendChild( xmldoc.CreateElement(“http://schemas.xmlsoap.org/soap/envelope/” ,“soapenv:Envelope”) )
firstnode = root.AppendChild(xmldoc.CreateElement(“soapenv:Body”))
seconnnode = firstnode.AppendChild(xmldoc.CreateElement(urn1:METHOD1"))

Its giving me exception in seconnnode = firstnode.AppendChild(xmldoc.CreateElement(urn1:METHOD1"))
and also how do i add more attibutes to soapenv:Envelope as if i’m doing
root.setAttribute “urn:schemas-iwaysoftware-com:iwse”, “urn:iwaysoftware:ibse:jul2003:METHOD1”
its giving me exception and application is crashing .

Thanks
IP

try
xmldoc.DocumentElement.SetAttribute(“xmlns:urn”,“urn:schemas-iwaysoftware-com:wise”)
xmldoc.DocumentElement.SetAttribute(“xmlns:urn1”,“urn:iwaysoftware:ibse:jul2003:EPQWebService_T1”)

and then add the “urn1:METHOD” node

Thank you so much Antonio, I have tried most of the options except for this.