The existing XML construct from buffer does not attach the new objects to the correct base object.  This results in not being able to register for events on the base object, since they are not passed in.

The problem is its use of glade_xml_new_from_buffer, which creates a new object instead of attaching to the existing one.  Bug 326511 has been entered with a patch to add glade_xml_construct_from_buffer to libglade.  This patch switches the XML construct from buffer method to use that new method, thereby fixing the problem.

Here is the patch:

--- libglademm-2.6.1/libglade/libglademm/xml.cc 2006-01-09 18:27:30.000000000 -0500
+++ libglademm-2.6.1/libglade/libglademm/xml.cc_new     2006-01-09 18:27:15.000000000 -0500
@@ -70,15 +70,16 @@
   }
 }

-// TODO: we need glade_xml_construct_from_buffer()
 Xml::Xml(const char* buffer, int size, const Glib::ustring& root, const Glib::ustring& domain)
 :
-  Glib::ObjectBase(0),
-  Glib::Object((GObject*) glade_xml_new_from_buffer(
-      buffer, size, root.empty() ? 0 : root.c_str(), domain.empty() ? 0 : domain.c_str()))
-{
-  if(!gobj())
+  Glib::ObjectBase(0), //Mark this class as gtkmmproc-generated, rather than a custom class, to allow vfunc optimisations.
+  Glib::Object(Glib::ConstructParams(xml_class_.init(), (char*) 0))
+{
+  if(!glade_xml_construct_from_buffer(gobj(), buffer, size, root.empty()   ? 0 : root.c_str(),
+                                                    domain.empty() ? 0 : domain.c_str()))
+  {
     throw XmlError("Failed to read glade input buffer");
+  }
 }

 // static