function Login(AKennung, APasswort: string): Boolean;
const
  IEFields: array[1..4] of string = ('INPUT', 'text', 'INPUT', 'password');
var
  ShellWindow: IShellWindows;
  WB: IWebbrowser2;
  spDisp: IDispatch;
  IDoc1: IHTMLDocument2;
  Document: Variant;
  k, m: Integer;
  ovElements: OleVariant;
  i: Integer;
  IEFieldsCounter: Integer;
begin
  ShellWindow := CoShellWindows.Create;
  // get the running instance of Internet Explorer
  for k := 0 to ShellWindow.Count do
  begin
    spDisp := ShellWindow.Item(k);
    if spDisp = nil then Continue;
    // QueryInterface determines if an interface can be used with an object
    spDisp.QueryInterface(iWebBrowser2, WB);
    if WB <> nil then
    begin
      WB.Document.QueryInterface(IHTMLDocument2, iDoc1);
      if iDoc1 <> nil then
      begin
        WB := ShellWindow.Item(k) as IWebbrowser2;
        Document := WB.Document;

        if Pos('', Document.Title) <> 0 then
          // count forms on document and iterate through its forms
          IEFieldsCounter := 0;
          for m := 0 to Document.forms.Length - 1 do
          // Document.forms.Length ist 0 und somit wird die schleife nie durchlaufen
          begin
            ovElements := Document.forms.Item(m).elements;

            // iterate through elements
            for i := ovElements.Length - 1 downto 0 do
            begin
              try
              // if input fields found, try to fill them out
                if (ovElements.item(i).tagName = IEFields[1]) and
                  (ovElements.item(i).type = IEFields[2]) then
                  begin
                    ovElements.item(i).Value := AKennung;
                    inc(IEFieldsCounter);
                  end;

                if (ovElements.item(i).tagName = IEFields[3]) and
                  (ovElements.item(i).type = IEFields[4]) then
                  begin
                    ovElements.item(i).Value := APasswort;
                    inc(IEFieldsCounter);
                  end;
              except
                // failed...
              end;
            end; { for i...}
          end; { for m }
      end; { idoc <> nil }
    end; { wb <> nil }
    // if the fields are filled in, submit.
    if IEFieldsCounter = 3 then ExecuteScript(iDoc1, 'document.login.submit()', 'JavaScript');
  end; { for k }
end;

<form action="/index.php?action=login" method=POST>

Benutzername:
<input type="text" name="member">

Passwort:
<input type="password" name="pass">

Server:
<select name="server">
  <option value="1">Server 1</option>
  <option value="2">Server 2</option>
</select>

<input type="submit" value="anmelden">

</form>