This really should be handled by GTK, as the default keystroke handler for the tabs (aka GtkNotebook) is Ctrl+PageUp and Ctrl+PageDown.
However, here is a sample patch (against nautilus 2.26.2) to get Ctrl+Tab and Ctrl+Shift+Tab to have the same functionality; it's a bit of a hack.
This really should be handled by GTK, as the default keystroke handler for the tabs (aka GtkNotebook) is Ctrl+PageUp and Ctrl+PageDown.
However, here is a sample patch (against nautilus 2.26.2) to get Ctrl+Tab and Ctrl+Shift+Tab to have the same functionality; it's a bit of a hack.