How to define type of respone for my webservice

[sergiobotta]

I am new in VB.NET webservices. I have created this WS:

<%@ WebService Language="vb" Class="Service" %>
Imports System.Web.Services
Imports System.Net
Imports System.IO
Imports System.Xml
<WebService(Namespace:="[URL unfurl="true"]http://nnn.nnn.nnn.nnn/ws/WSName")>[/URL]
<WebServiceBinding(ConformsTo:=WsiProfiles.BasicProfile1_1)> _
<Global.Microsoft.VisualBasic.CompilerServices.DesignerGenerated()> _
Public Class Service
Inherits System.Web.Services.WebService 
<WebMethod()>
Public Function FunctionToCall(ByVal usuario As String, ByVal clave As String) As XmlDocument
    <my code here>
    Dim inicioXML As string = "<RespuestaDelServicio xmlns=""[URL unfurl="true"]http://nnn.nnn.nnn.nnn/ws/WSName"">"[/URL]
    Dim finXML As string = "</RespuestaDelServicio>"
    Dim xmlResponse As String = "<data>....</data>"
    Dim cuerpoXML As String = inicioXML & xmlResponse & finXML
    Dim XMLdoc2 As New XmlDocument
    XMLdoc2.LoadXml(cuerpoXML)
    Dim xmldecl As XmlDeclaration
    xmldecl = XMLdoc2.CreateXmlDeclaration("1.0", Nothing, Nothing)
    xmldecl.Encoding = "UTF-8"  
    xmldecl.Standalone = "yes"
    Dim root As XmlElement = XMLdoc2.DocumentElement 
    XMLdoc2.InsertBefore(xmldecl, root)
    Return XMLdoc2
End Function

When I try it in SoapUI, the result seems to be Ok, but If I validate it using ALT+V I receive the error: "line 5: Element not allowed (strict wildcard, and no definition found)". It seems that I have to define processContents to 'lax' so SoapUI does not try to validate my response against a XSD file.

Link

But I don´t know how to define it on my code. Thanks a lot!