Well, from http://glade.gnome.org/

"By using libglade, Glade XML files can be used in numerous programming languages including C, C++, Java, Perl, Python, C#, Pike, Ruby, Haskell, Objective Caml and Scheme."

And for Perl there would Gtk2-GladeXML. Though, I've never used any of those. Was just a quick lookup.