Gtk::Calendar problem

["Nikolay Shibalov" <networm87 gmail com>]

Hi. The problem is when i dynamically(then press a button for example) add  page containing Gtk::Calendar to Gtk::Notebook, Gtk::Calendar widget is partially visible through the first page, until I switch all tabs. 

  The problem appears only with dynamic page addition(if i do this in constructor all ok) and  may be only with Gtk::Calendar.

Gtkmm version: gtkmm-2.12.5 built under MS Visual C++ Express 2008.
OS: MS Vista x64.

//---Code 

void ExampleWindow::on_button_add()
{
    m_pNotebook->append_page(*Gtk::manage(new Gtk::Calendar()), "Calendar");
    show_all_children();
} 

//-------- 

Sorry for my bad english.