def to_xml
      if signature? and signature.have_document?
        Gyoku.xml wsse_signature.merge!(hash)
      elsif username_token? && timestamp?
        Gyoku.xml wsse_username_token.merge!(wsu_timestamp) {
          |key, v1, v2| v1.merge!(v2) {
            |key, v1, v2| v1.merge!(v2)
          }
        }
      elsif username_token?
        Gyoku.xml wsse_username_token.merge!(hash)
      elsif timestamp?
        Gyoku.xml wsu_timestamp.merge!(hash)
      else
        ""
      end
    end
def to_xml
      if signature? and signature.have_document?
        Gyoku.xml wsse_signature.merge!(hash)
      elsif username_token? && timestamp?
        Gyoku.xml wsse_username_token.merge!(wsu_timestamp) {
          |key, v1, v2| v1.merge!(v2) {
            |key, v1, v2| v1.merge!(v2)
          }
        }
      elsif username_token?
        Gyoku.xml wsse_username_token.merge!(hash)
      elsif timestamp?
        Gyoku.xml wsu_timestamp.merge!(hash)
      else
        ""
      end
    end
Returns the XML for a WSSE header.