Gtk+ 1.1.5 gtktoolbar bug ?

[Mario Motta <mmotta guest net>]

hi all,
seems that in gtk+ 1.1.5 a code like this:
=================================================================
widget = gtk_toolbar_new(orientation,GTK_TOOLBAR_ICONS);
button = gtk_toolbar_append_item (GTK_TOOLBAR (widget),
                                    text, 
                                    tip,
                                    NULL,
                                    pixmap,
                                    GTK_SIGNAL_FUNC(ButtonSignal),
                                    (gpointer) data);
gtk_widget_set_sensitive(button,FALSE);
=================================================================
gets this gdk message:
Gdk-CRITICAL **:
file gdkdraw.c: line 312 (gdk_draw_pixmap): assertion `src != NULL'
failed.
After that no pixmap appears over button.

With "gtk_widget_set_sensitive(button,TRUE);"
or commenting out offending line situation returns normal.
Does the button needs a pixmap also for insensitive state ?
Previous gtk+ version did not show this behaviour. Point me in right
direction, please.

regards
-- 
Mario Motta
AI Research Group - Rimini
mmotta@guest.net
http://www.guest.net/homepages/mmotta/VDKHome/index.htm