Hi,  I am attempting to call the set_shadow_type for a menubar and it does not work.  
Here's the error message I am getting:
assist.rbw:14:in `initialize': undefined method `set_shadow_type' for #<Gtk::Men
uBar:0x282dc68> (NameError)
        from assist.rbw:257:in `new'
        from assist.rbw:257
However, in my Gtk+ book, it appears that this IS a method of menubar.  What am I doing wrong?