调用应用服务器上的函数出问题，求救高手！！！！

我在应用服务器上写了一个过程，用于创建树，代码如下：
procedure TRM_APPServer.CreateTree(out TreeName: HResult);
Var
AreaTree:TTreeView;
Query :TADOQuery;
TopoNode,AreaNode,JuzhNode,JishNode:TTreeNode;
begin
AreaTree:=TTreeView.Create(nil);
With AreaTree do
begin
//Images:=
Items.Clear;
TopoNode:=Items.Add(nil,'.....');
//ToPoNode.ImageIndex:=
Query:=TADOQuery.Create(nil);
With Query do
begin
Close;
Sql.Clear;
Sql.Add('Select * From SUB_DISTRICT');
Open;
While Not Eof do
begin
New(AreaID);
AreaID.Code:=Fields[0].AsInteger;
AreaID.Desc:=Fields[1].AsString;
AreaNode:=Items.AddChildObject(TopoNode,Fields[1].AsString,AreaID);
Next;
end;
..............
end;
Query.Free;
end;
end;
我在客户端调用它，代码如下：
DCOMConnection1.AppServer.CreateTree(@TreeView1);
编译时系统出错：
Type not allow in Variant Dispatch Call
特请各路神仙指点迷津