关于delphi写的客户端调用java 写的web service问题(100分)

客户端应该怎么写阿？请教一下
procedure TForm1.Button1Click(Sender: TObject);
var
p : TradeIF;
begin
p := HTTPRIO1 As TradeIF;
Edit1.Text := p.entruststock('aaa');
end;
////////////
wsdl生成的接口如下：
interface

uses Types, XSBuiltIns;
type

TradeIF = interface(IInvokable)
['{E909B54F-3D0F-4EE1-BCB9-C89F428E2B48}']
procedure accountensure(const String_1: WideString; out result: WideString); stdcall;
procedure entrustcancel(const String_1: WideString; out result: WideString); stdcall;
procedure entrustensure(const String_1: WideString; out result: WideString); stdcall;
procedure entrustprice(const String_1: WideString; out result: WideString); stdcall;
// procedure entruststock(const String_1: WideString; out result: WideString); stdcall;
function entruststock(const String_1: WideString):WideString; stdcall;
procedure querybusiness(const String_1: WideString; out result: WideString); stdcall;
procedure queryentrust(const String_1: WideString; out result: WideString); stdcall;
procedure queryentrustcancel(const String_1: WideString; out result: WideString); stdcall;
procedure queryfund(const String_1: WideString; out result: WideString); stdcall;
procedure queryhq(const String_1: WideString; out result: WideString); stdcall;
procedure querystock(const String_1: WideString; out result: WideString); stdcall;
end;
implementation

现在安装了delphi6 sp2以后，变成这个错误：
xml文档必须有一个 顶层元素