Attachment Webservices

Hello,
I'm trying to play with a basic webservice to insert an attachment (URL) via a web service.

My syntax is below.

<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:wsse="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-secext-1.0.xsd" xmlns:ns="urn:crmondemand/ws/ecbs/servicerequest/10/2004" xmlns:data="urn:/crmondemand/xml/ServiceRequest/Data">
   <soapenv:Header>
    <wsse:Security soapenv:mustUnderstand="1">
    <wsse:UsernameToken>
        <wsse:Username>sampleusername</wsse:Username>
        <wsse:Password Type="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-username-token-profile-1.0#PasswordText">samplepassword</wsse:Password>
    </wsse:UsernameToken>
    </wsse:Security>
   </soapenv:Header>
   <soapenv:Body>
      <ns:ServiceRequestInsert_Input>
         <data:ListOfServiceRequest>
            <!--Zero or more repetitions:-->