Comment 2 for bug 810145

StacktraceTop:
 g_type_check_instance_cast (type_instance=0xb6237d98, iface_type=138005672) at /build/buildd/glib2.0-2.29.10/./gobject/gtype.c:3985
 gail_widget_notify_gtk (obj=0x8332008, pspec=0x82ac260) at /build/buildd/gtk+3.0-3.1.8/./modules/other/gail/gailwidget.c:954
 g_cclosure_marshal_VOID__PARAM (closure=0x839e600, return_value=0x0, n_param_values=2, param_values=0x83a3028, invocation_hint=0xbfd38570, marshal_data=0x0) at /build/buildd/glib2.0-2.29.10/./gobject/gmarshal.c:539
 g_closure_invoke (closure=0x839e600, return_value=0x0, n_param_values=2, param_values=0x83a3028, invocation_hint=0xbfd38570) at /build/buildd/glib2.0-2.29.10/./gobject/gclosure.c:773
 signal_emit_unlocked_R (node=0x8286f18, detail=433, instance=0x8332008, emission_return=0x0, instance_and_params=0x83a3028) at /build/buildd/glib2.0-2.29.10/./gobject/gsignal.c:3256