Unbind shift-pageup in VteTerminal

[Cory Sharp <cory sentilla com>]

Hi.  I need some help.  I'm trying to unbind Shift-PageUp in
gnome-terminal, which I believe uses VteTerminal.  I'm using Ubuntu
9.04 with libgtk 2.16.1.  I've read the GTK "Bindings" documentation
and placed the following in my ~/.gtkrc-2.0 file

    binding "NoScrollback" {
        unbind "<shift>Page_Up"
        unbind "<shift>KP_Page_Up"
    }
    class "VteTerminal" binding "NoScrollback"

After restarting X, the key still seems to be bound.  Is there
something I'm doing wrong?  Any help or insight is appreciated.

Thanks!
Cory