Problem with filechooser (defined with Glade)

Hi list. I'm new to PHP-GTK and try to use it with Glade-2. (PHP version is 5.2.2 and PHP-GTK module is 2.0.0beta). I run Linux F7. In Glade, I define a main window with some children and a FileChooser set to be invisible until I need it. When the user chooses 'Open' in the menu bar of the main window, I call $FileChooser->set_visible(true) and it works. When the FileChooser is closed, I call $FileChooser->set_visible(false) and it works also. However the next call to $FileChooser->set_visible(true) won't correctly redraw the file chooser widget: only the background of the widget is drawn. If I do a pair of set_visible(false)/(true) again on it, only the title of the file chooser window is drawn. I'm new to GUI and PHP-GTK so I probably miss something obvious, or my way of using Glade and the filechooser is wrong.. Any hint welcome! Thanks! Bernard