GTK Modal dialog

["Miroslav Rajcic" <rajcic sokrates hr>]

I am trying to show the dialog in a modal way.
I've read in some old posts that the way to do it is like this:

 //show dialog
 gtk_widget_show(dialog1);
 gtk_grab_add(dialog1); //disable everything except this dialog
 gtk_main();  //block in modal state until dialog terminates

 //cleanup
 gtk_grab_remove(dialog1);
 gtk_widget_destroy(dialog1);

My problem is that dielog doesn't seem modal at all. When I click on its
parent window, dialog falls back underneath all other windows on the
desktop.
Even setting this doesn't help:
gtk_window_set_modal (GTK_WINDOW (dialog1), TRUE);
gtk_window_set_keep_above(GTK_WINDOW (dialog1), TRUE);

My platform is Win32, gtk-2.4.9

Does anyone know what could be wrong here ?

TIA,
   Miroslav Rajcic