Iterating through datamodule components fails with persistent fields

Hi,

I have a piece of code on a OnCreate event of a datamodule which looks as follows:

----------------------
  try
    if not SS.Active then
      SS.Active := TRUE;

    DB.Connected    := FALSE;
    DB.SessionName  := SS.SessionName;
    DB.DatabaseName := 'DB' + SS.SessionName;
    DB.Connected    := TRUE;


    for I := 0 to (ComponentCount - 1) do
    begin
      if (Components [I] is TTable) then
      try
        TTable (Components [I]).Active       := FALSE;
        TTable (Components [I]).SessionName  := SS.SessionName;
        TTable (Components [I]).DataBaseName := DB.DatabaseName;
        TTable (Components [I]).Active       := TRUE;
      except
        ...
        raise;
      end;
      if (Components [I] is TQuery) then
      try
        TQuery (Components [I]).Close;
        TQuery (Components [I]).SessionName  := SS.SessionName;
        TQuery (Components [I]).DataBaseName := DB.DatabaseName;
      except
        ...
        raise;
      end;
    end;

    QEmpSel.Active  := TRUE;
    QEmpresa.Active := TRUE;

  except
    ShowMessage ('ERROR');
    Application.Terminate;
  end;
-------------------
(Hope you can see it OK)

What is makes is to assign the session and database names to all the tables and queries in the data module.

Well, it works ONLY IF THERE IS NO PERSISTENT FIELDS IN THE TABLES.

I mean, if I click twice on a table and add all fields (or even only one) onto the fields editor, it stops working.

WHY?
HOW TO CORRECT THIS BEHAVIOUR?

Thanks