diff -Nurd ../freeciv/client/gui-gtk/graphics.c ./client/gui-gtk/graphics.c
--- /tmp/freeciv/client/gui-gtk/graphics.c	Wed Sep 29 12:46:28 1999
+++ ./client/gui-gtk/graphics.c	Mon Oct  4 14:01:22 1999
@@ -295,6 +295,11 @@
   
   pm=gdk_pixmap_new(root_window, NORMAL_TILE_WIDTH, NORMAL_TILE_HEIGHT, -1);
 
+  /* use -1 if you just want a tile, e.g. if the units aren't known yet */
+  if (i == -1) {
+    return;
+  }
+
   /* Give tile a background color, based on the type of unit */
   switch (get_unit_type(i)->move_type) {
     case LAND_MOVING: bg_color = COLOR_STD_GROUND; break;
diff -Nurd ../freeciv/client/gui-gtk/helpdlg.c ./client/gui-gtk/helpdlg.c
--- /tmp/freeciv/client/gui-gtk/helpdlg.c	Sun Oct  3 12:46:42 1999
+++ ./client/gui-gtk/helpdlg.c	Mon Oct  4 14:01:43 1999
@@ -325,7 +325,7 @@
   gtk_container_add( GTK_CONTAINER( help_frame ), help_box );
 
 
-  unit_tile = gtk_pixmap_new( create_overlay_unit( 0 ), NULL );
+  unit_tile = gtk_pixmap_new( create_overlay_unit( -1 ), NULL );
   gtk_box_pack_start( GTK_BOX( help_box ), unit_tile, FALSE, FALSE, 0 );