WCF / ASMX :: Cannot Return Typed Datatable From WebService

I can fill and then return typed dataset from a web method, but applying these steps by using Typed Datatable instead of Typed Dataset I cannot return filled typed dataTable. So, is it possible to return typed dataTable from a web method? If yes, how can I do this?

I shall give a little bit information about my project. There is 3 project in my solution.
I) Presentation Layer (WinForm), II) Business Layer (Web Service) ,
III) Data Access Layer (Win form project type)... The problem is that;

I use 2 seperate methods. 1st is FillTable() which fill a datatable in my Typed Dataset in Data Access layer. The 2nd isGetTable() which should return typed datatable filled by FillTable() method. I try these methods and FillTable() methods (goes from I. layer to II. Layer and then III. layer) fills a datatable properly and after that I can return this datatable by calling GetTable() method from Typed Dataset (in III. layer) to WebService. I have tested the rows count of returning datatable and there is no problem up to WebService. But even after returning this typed datatable from WebService the table comes to Presentation Layer empty. So, there is a problem returning filled typed datatable from WebService to WebForm (from II. layer to I. layer).

On the other hand, if I try this methods by returning Typed Dataset instead of Typed Datatable, I can return properly with a filled datatable in Typed Dataset. But, I relly do not want to return a huge filled dataset which may contain 15 tables instead of one datatable. My questions;

1) Is there any logical approach mistake on my Layer Architecture?

2) What should I do in order to get a Typed Datatable from Web Service (II. Layer of my project)?