Stock icons in resource files

[root <root p15122568 pureserver info>]

The following problem is in 2.10.1, and may have been around for some
versions previously, although things worked okay in the relatively
distant past (2.0?).

My gtk.rc file contains

=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=--=-
pixmap_path "/install/share/lcm-tablet/graphics"

style "lcm-tablet-stock"
{
   stock["compass-gps"] = { { "compass-icon.png" } }
   stock["satellites"] = { { "satellites.png" } }
}

class  "GtkWidget"       style "lcm-tablet-stock"
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=--=-

as well as some other stuff which works perfectly.  I am trying to
load the icons into toolbar toggle buttons, but I just see white boxes
with red crosses.  No error messages anywhere.


Snippets of my code include

=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=--=-
static GtkRadioActionEntry menu_gps_radio []
= { { "Compass", "compass-gps", "_Compass", "<control>C",
      "Touch the compass rose to move around on the map", 0 },
    { "GPS", "satellites", "_GPS", "<control>G",
      "The map will be centred based on information from the GPS receiver", 2 }
  };
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=--=-

and then

=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=--=-
  gtk_action_group_add_radio_actions
    (actions, 
     menu_gps_radio, G_N_ELEMENTS (menu_gps_radio), 
     2, 
     G_CALLBACK (gps_radio_source_changed),
     tablet);
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=--=-


Everything works perfectly apart from the icons not showing up.  Any
ideas anyone?