diff -Nur -Xdiff_ignore freeciv_cvs/server/unithand.c freeciv/server/unithand.c
--- freeciv_cvs/server/unithand.c	Thu Jan 11 14:42:04 2001
+++ freeciv/server/unithand.c	Sun Jan 28 17:14:56 2001
@@ -125,7 +125,8 @@
   unit_list_iterate(pplayer->units, punit) {
     if (cost > pplayer->economic.gold)
       break;
-    if (punit->type == packet->type && map_get_city(punit->x, punit->y)) {
+    if (punit->type == packet->type && map_get_city(punit->x, punit->y) &&
+				map_get_city(punit->x, punit->y)->owner == pplayer->player_no) {
       pplayer->economic.gold -= cost;
       
       upgrade_unit(punit, to_unit);
@@ -157,6 +158,7 @@
   
   if(!(punit=player_find_unit_by_id(pplayer, packet->unit_id))) return;
   if(!(pcity=find_city_by_id(packet->city_id))) return;
+  if(!(pcity->owner == pplayer->player_no)) return; /* Allied city! */
 
   if(punit->x!=pcity->x || punit->y!=pcity->y)  {
     notify_player(pplayer, _("Game: Illegal move, unit not in city!"));