making GtkEntry *look* uneditable

[<shark centibyte org>]

Hello,

  After setting a GtkEntry to be not editable with
  gtk_editable_set_editable(GTK_EDITABLE(entry), FALSE); the entry widget
  still looks editable when the user runs the app (their is no visual
  difference between editable and non-editable).  I would hope it possible
  to make the base color grey (or whichever color is default background
  for labels and other non-editable things).  Is there any way to change
  this, either from inside the application or from a theme?
My current solution is to use
gtk_widget_modify_base(entry, GTK_STATE_NORMAL, &base_color);  but if that
is the best solution my question is, how can I set base_color to be the
same as the background color of other widgets (like labels)?
 Thanks!

 -Peter W