-        gdk_draw_polygon( pizza->bin_window, style->base_gc[GTK_STATE_NORMAL], TRUE, points, 3);
-    gdk_draw_polygon( pizza->bin_window, style->fg_gc[GTK_STATE_NORMAL], FALSE, points, 3 );
-#else
-    // this draws the GTK+ 2.2.3 tree item square    
-    gdk_draw_rectangle( pizza->bin_window,
-        style->base_gc[GTK_STATE_NORMAL], TRUE,
-        x, y, PM_SIZE, PM_SIZE);
-    gdk_draw_rectangle( pizza->bin_window,
-        style->fg_gc[GTK_STATE_NORMAL], FALSE,
-        x, y, PM_SIZE, PM_SIZE);
-
-    gdk_draw_line( pizza->bin_window, style->fg_gc[GTK_STATE_NORMAL],
-        x + 2, y + PM_SIZE / 2, x + PM_SIZE - 2, y + PM_SIZE / 2);
-
-    if ( flags & wxCONTROL_EXPANDED )
-    {
-        gdk_draw_line( pizza->bin_window, style->fg_gc[GTK_STATE_NORMAL],
-               x + PM_SIZE / 2, y + 2,
-               x + PM_SIZE / 2, y + PM_SIZE - 2);
-    }
-#endif    
-    
-    
-#else
-    dc.SetBrush(wxBrush(wxSystemSettings::GetColour(wxSYS_COLOUR_HIGHLIGHT),
-                        wxSOLID));
-    dc.SetPen(*wxBLACK_PEN);
-    wxPoint button[3];
-
-    const wxCoord xMiddle = rect.x + rect.width/2;
-    const wxCoord yMiddle = rect.y + rect.height/2;
-
-    if ( flags & wxCONTROL_EXPANDED )
-    {
-        button[0].x = rect.GetLeft();
-        button[0].y = yMiddle - 2;
-        button[1].x = rect.GetRight();
-        button[1].y = yMiddle - 2;
-        button[2].x = xMiddle;
-        button[2].y = yMiddle + 3;
-    }
-    else // collapsed
-    {
-        button[0].y = rect.GetBottom();
-        button[0].x = xMiddle - 2;
-        button[1].y = rect.GetTop();
-        button[1].x = xMiddle - 2;
-        button[2].y = yMiddle;
-        button[2].x = xMiddle + 3;
-    }
-
-    dc.DrawPolygon(3, button);
-#endif
+        state = GTK_STATE_NORMAL;
+        
+    // VZ: I don't know how to get the size of the expander so as to centre it
+    //     in the given rectangle, +2/3 below is just what looks good here...
+    gtk_paint_expander
+    (
+        tree->style,
+        GTK_PIZZA(win->m_wxwindow)->bin_window,
+        state,
+        NULL,
+        tree,
+        "treeview",
+        dc.LogicalToDeviceX(rect.x) + 2,
+        dc.LogicalToDeviceY(rect.y) + 3,
+        flags & wxCONTROL_EXPANDED ? GTK_EXPANDER_EXPANDED
+                                   : GTK_EXPANDER_COLLAPSED
+    );