diff -ur -Xfreeciv/diff_ignore freeciv/ai/advdomestic.c freeciv-mod/ai/advdomestic.c
--- freeciv/ai/advdomestic.c	Thu May 11 00:44:46 2000
+++ freeciv-mod/ai/advdomestic.c	Thu May 11 00:54:42 2000
@@ -403,7 +403,7 @@
 /* military advisor will deal with CITY and PORT */
 
   for (i = 0; i < B_LAST; i++) {
-    if (is_wonder(i) && could_build_improvement(pcity, i) && !wonder_obsolete(i)) {
+    if (is_wonder(i) && could_build_improvement(pcity, i) && !wonder_obsolete(i)&& is_wonder_usefull(i)) {
       if (i == B_ASMITHS)
         for (j = 0; j < B_LAST; j++)
           if (city_got_building(pcity, j) && improvement_upkeep(pcity, j) == 1)
diff -ur -Xfreeciv/diff_ignore freeciv/common/city.c freeciv-mod/common/city.c
--- freeciv/common/city.c	Thu May 11 00:44:52 2000
+++ freeciv-mod/common/city.c	Thu May 11 01:04:25 2000
@@ -310,6 +310,16 @@
 }
 
 /**************************************************************************
+Barbarians don't get enough knowledges to be counted as normal players.
+**************************************************************************/
+
+int is_wonder_usefull(Impr_Type_id id)
+{
+  if ((id == B_GREAT) && (get_nb_human_and_ai_players () < 3)) return 0;
+  return 1;
+}
+
+/**************************************************************************
 ...
 **************************************************************************/
 
diff -ur -Xfreeciv/diff_ignore freeciv/common/city.h freeciv-mod/common/city.h
--- freeciv/common/city.h	Thu May 11 00:44:57 2000
+++ freeciv-mod/common/city.h	Thu May 11 01:01:19 2000
@@ -256,6 +256,7 @@
 int improvement_obsolete(struct player *pplayer, Impr_Type_id id);
 struct improvement_type *get_improvement_type(Impr_Type_id id);
 int wonder_obsolete(Impr_Type_id id);
+int is_wonder_usefull(Impr_Type_id id);
 int is_wonder(Impr_Type_id id);
 int improvement_exists(Impr_Type_id id);
 Impr_Type_id find_improvement_by_name(char *s);
diff -ur -Xfreeciv/diff_ignore freeciv/common/game.c freeciv-mod/common/game.c
--- freeciv/common/game.c	Thu May 11 19:42:40 2000
+++ freeciv-mod/common/game.c	Thu May 11 19:58:15 2000
@@ -755,6 +755,7 @@
   game.auto_ai_toggle = GAME_DEFAULT_AUTO_AI_TOGGLE;
   game.barbarianrate  = GAME_DEFAULT_BARBARIANRATE;
   game.onsetbarbarian = GAME_DEFAULT_ONSETBARBARIAN;
+  game.nbarbarians = 0;
   game.occupychance= GAME_DEFAULT_OCCUPYCHANCE;
   game.heating     = 0;
   sz_strlcpy(game.save_name, "civgame");
@@ -890,6 +891,8 @@
 {
   struct player *pplayer=&game.players[plrno];
 
+  if (is_barbarian(pplayer)) game.nbarbarians--;
+  
   unit_list_iterate(pplayer->units, punit) 
     game_remove_unit(punit->id);
   unit_list_iterate_end;
@@ -942,6 +945,14 @@
     return &game.players[player_id];
 }
 
+/**************************************************************************
+This function is used by is_wonder_usefull to estimate if it is worthwhile
+to build the great library.
+**************************************************************************/
+int get_nb_human_and_ai_players(void)
+{
+return game.nplayers-game.nbarbarians;
+}
 
 /***************************************************************
   For various data, copy eg .name to .name_orig and put
diff -ur -Xfreeciv/diff_ignore freeciv/common/game.h freeciv-mod/common/game.h
--- freeciv/common/game.h	Thu May 11 00:45:07 2000
+++ freeciv-mod/common/game.h	Thu May 11 00:54:59 2000
@@ -57,6 +57,7 @@
   int aifill;
   int barbarianrate;
   int onsetbarbarian;
+  int nbarbarians;
   int occupychance;
   int unhappysize;
   char *startmessage;
@@ -161,6 +162,7 @@
 void translate_data_names(void);
 
 struct player *get_player(int player_id);
+int get_nb_human_and_ai_players (void);
 
 extern struct civ_game game;
 
diff -ur -Xfreeciv/diff_ignore freeciv/server/barbarian.c freeciv-mod/server/barbarian.c
--- freeciv/server/barbarian.c	Thu May 11 00:45:12 2000
+++ freeciv-mod/server/barbarian.c	Thu May 11 00:55:04 2000
@@ -165,6 +165,7 @@
   init_tech(barbarians, game.tech);
 
   game.nplayers++;
+  game.nbarbarians++;
   game.max_players = game.nplayers;
 
   freelog(LOG_VERBOSE, "Created barbarian %s, player %d", barbarians->name, 
diff -ur -Xfreeciv/diff_ignore freeciv/server/gamehand.c freeciv-mod/server/gamehand.c
--- freeciv/server/gamehand.c	Wed May 10 21:26:24 2000
+++ freeciv-mod/server/gamehand.c	Thu May 11 20:08:57 2000
@@ -374,6 +374,8 @@
 						  "game.barbarians");
   game.onsetbarbarian = secfile_lookup_int_default(file, game.onsetbarbarian,
 						   "game.onsetbarbs");
+  game.nbarbarians = 0; /* counted in player_load for compatibility with 
+			   1.10.0 */
   game.occupychance = secfile_lookup_int_default(file, game.occupychance,
   						 "game.occupychance");
   
diff -ur -Xfreeciv/diff_ignore freeciv/server/plrhand.c freeciv-mod/server/plrhand.c
--- freeciv/server/plrhand.c	Wed May 10 21:26:24 2000
+++ freeciv-mod/server/plrhand.c	Thu May 11 20:00:38 2000
@@ -1978,6 +1978,7 @@
 
   plr->ai.is_barbarian = secfile_lookup_int_default(file, 0, "player%d.ai.is_barbarian",
                                                     plrno);
+  if (is_barbarian(plr)) game.nbarbarians++;
 
   sz_strlcpy(plr->name, secfile_lookup_str(file, "player%d.name", plrno));
   sz_strlcpy(plr->username,