gtk_object_sink in glade_palette_init

[Philippe Bertin <philippe bertin telenet be>]

Hello,

This question could've gone to the glade list. But the explanation may 
help GTK programmers in general (I think), so I rather ask it here.

In glade_palette_init, there's this piece of code :

   /* Add items tray (via a scrolled window) */
   priv->tray = gtk_vbox_new (FALSE, 0);
   g_object_ref (G_OBJECT (priv->tray));
   gtk_object_sink (GTK_OBJECT (priv->tray));

What's the goal of this gtk_object_sink ? I thought that after 
glade_palette_init returns, the local references are gone ? Is there a 
subtlety I don't get ?

Kind regards,

PhB

P.S. Looking for the meaning of the gtk_object_sink call, at 
http://developer.gnome.org/doc/API/2.0/gtk/GtkObject.html#gtk-object-sink 
I see it's deprecated. g_object_ref_sink should be called instead 
(according to the gtk help) ?