diff -ru freeciv/ai/aiunit.c freeciv+pasky/ai/aiunit.c
--- freeciv/ai/aiunit.c	Sat Nov 24 00:42:27 2001
+++ freeciv+pasky/ai/aiunit.c	Sat Nov 24 21:05:01 2001
@@ -177,24 +177,23 @@
 }
  
 /**************************************************************************
-Explores unknown territory, finds huts.
+Handle eXplore mode of a unit - explores unknown territory, finds huts.
 Returns whether there is any more territory to be explored.
 **************************************************************************/
-int ai_manage_explorer(struct unit *punit)
+int ai_manage_exploring(struct unit *punit)
 {
   struct player *pplayer = unit_owner(punit);
-  int x, y; /* is the position of the unit; updated inside the function */
-  int con; /* continent the unit is on */
-  struct city *pcity;
+  int x, y; /* the position of the unit; updated inside the function */
+  int continent; /* continent the unit is on */
   int id = punit->id; /* we can now die because easy AI may accidently
 			 stumble on huts it fuzzily ignored */
-  int best_x = -1, best_y = -1;
+  int best_x = -1, best_y = -1; /* desired destination */
   int move_rate = unit_move_rate(punit);
-  int range;
+  int range; /* range of unit's vision */
 
   if (unit_profits_of_watchtower(punit)
       && map_get_tile(punit->x, punit->y)->special & S_FORTRESS)
-    range =get_watchtower_vision(punit);
+    range = get_watchtower_vision(punit);
   else
     range = unit_type(punit)->vision_range;
 
@@ -202,17 +201,19 @@
     handle_unit_activity_request(punit, ACTIVITY_IDLE);
 
   x = punit->x; y = punit->y;
-  if (is_ground_unit(punit)) con = map_get_continent(x, y);
-  else con = 0; /* Thanks, Tony */
+  if (is_ground_unit(punit)) continent = map_get_continent(x, y);
+  else continent = 0; /* ships don't care about continents */
 
   /* CPU-expensive but worth it -- Syela */
   generate_warmap(map_get_city(x, y), punit);
 
-  /* BEGIN PART ONE: Look for huts.  Non-Barbarian Ground units ONLY. */
+  /* PART ONE: Look for huts.
+   * Non-Barbarian Ground units ONLY.
+   */
   if (!is_barbarian(pplayer)
-      && is_ground_unit(punit)) { /* boats don't hunt huts */
+      && is_ground_unit(punit)) {
     int maxcost = pplayer->ai.control ? 2 * THRESHOLD : 3;
-    int bestcost = maxcost * SINGLE_MOVE + 1;
+    int bestcost = maxcost * SINGLE_MOVE + 1; /* lower is better */
 
     /* Iterating outward so that with two tiles with the same movecost
        the nearest is used */
@@ -227,6 +228,7 @@
 	bestcost = warmap.cost[best_x][best_y];
       }
     } iterate_outward_end;
+    
     if (bestcost <= maxcost * SINGLE_MOVE) {
       punit->goto_dest_x = best_x;
       punit->goto_dest_y = best_y;
@@ -235,15 +237,17 @@
       if (!player_find_unit_by_id(pplayer, id))
 	return 0; /* died */
 
+      /* We can still move on.. */
       if (punit->moves_left) {
+	/* ..and we got into desired place. */
 	if (punit->x == best_x && punit->y == best_y) {
-	  return ai_manage_explorer(punit);
+	  return ai_manage_exploring(punit);
 	} else {
 	  /* Something went wrong; fall through. This should almost never happen. */
 	  if (punit->x != x || punit->y != y)
 	    generate_warmap(map_get_city(punit->x, punit->y), punit);
 	  x = punit->x; y = punit->y;
-	  /* Fallthough to next fase */
+	  /* Fallthough to next phase */
 	}
       } else {
 	return 1;
@@ -251,28 +255,34 @@
     }
   }
 
-  /* BEGIN PART TWO: Move into unexplored territory */
-  /* move the unit as long as moving will unveil unknown territory */
+  /* PART TWO: Move into unexplored territory
+   * Move the unit as long as moving will unveil unknown territory
+   */
   while (punit->moves_left) {
-    int most_unknown = 0;
-    int unknown;
+    int most_unknown = 0; /* max. number of unknown tiles */
 
     /* evaluate all adjacent tiles */
     square_iterate(x, y, 1, x1, y1) {
-      unknown = 0;
+      int unknown = 0; /* number of unknown tiles reachable from this tile */
+      
+      /* and all tiles in our vision range around them */
       square_iterate(x1, y1, range, x2, y2) {
 	if (!map_get_known(x2, y2, pplayer))
 	  unknown++;
       } square_iterate_end;
 
+      /* We have to be careful with triremes, we won't travel to
+       * another continents, won't travel into cities (unless we
+       * are able to do so - diplomats and caravans can) and we
+       * won't raze huts if we are barbarians.
+       */
       if (unknown > most_unknown && (!unit_flag(punit, F_TRIREME)
 				     || trireme_loss_pct(pplayer, x1,
 							 y1) == 0)
-	  && map_get_continent(x1, y1) == con
+	  && map_get_continent(x1, y1) == continent
 	  && can_unit_move_to_tile_with_notify(punit, x1, y1, 0)
-	  && !((pcity = map_get_city(x1,y1))
-	       && (unit_flag(punit, F_DIPLOMAT)
-		   || unit_flag(punit, F_CARAVAN)))
+	  && !(map_get_city(x1,y1) &&
+	       (unit_flag(punit, F_DIPLOMAT) || unit_flag(punit, F_CARAVAN)))
 	  && !(is_barbarian(pplayer) && map_get_special(x1, y1) & S_HUT)) {
 	most_unknown = unknown;
 	best_x = x1;
@@ -280,43 +290,55 @@
       }
     } square_iterate_end;
 
-    if (most_unknown > 0) { /* a tile have unexplored territory adjacent */
+    /* a tile have unexplored territory adjectent, move there */
+    if (most_unknown > 0) {
       int res = handle_unit_move_request(punit, best_x, best_y, FALSE, FALSE);
       if (!res) /* This shouldn't happen */
 	break;
+      
       if (!player_find_unit_by_id(pplayer, id))
 	return 0; /* died */
       x = punit->x; y = punit->y;
     } else {
-      break;
+      break; /* we explored everything */
     }
   }
 
   if (!punit->moves_left) return 1;
 
-  /* BEGIN PART THREE: Go towards unexplored territory */
-  /* no adjacent squares help us to explore - really slow part follows */
+  /* PART THREE: Go towards unexplored territory
+   * No adjacent squares help us to explore - really slow part follows
+   */
   generate_warmap(map_get_city(x, y), punit);
 
   {
-    int unknown, most_unknown = 0;
-    int threshold = THRESHOLD * move_rate;
+    int most_unknown = 0; /* max. number of unknown tiles */
+    
     whole_map_iterate(x1, y1) {
       struct tile *ptile = map_get_tile(x1, y1);
-      unknown = 0;
-      if (ptile->continent == con
+      int threshold = THRESHOLD * move_rate;
+      int unknown = 0; /* number of unknown tiles reachable from this tile */
+      
+      /* We won't travel to another continents or into foreign occupied squares. */
+      if (ptile->continent == continent
 	  && !is_non_allied_unit_tile(ptile, pplayer)
 	  && !is_non_allied_city_tile(ptile, pplayer)
 	  && tile_is_accessible(punit, x1, y1)) {
+	
+        /* evaluate all tiles in our vision range around this tile */
 	square_iterate(x1, y1, range, x2, y2) {
 	  if (!map_get_known(x2, y2, pplayer))
 	    unknown++;
 	} square_iterate_end;
+	
 	if (unknown) {
+	  /* also care about how fast we can get there */
 	  if (is_sailing_unit(punit))
 	    unknown += 9 * (threshold - warmap.seacost[x1][y1]);
 	  else
 	    unknown += 9 * (threshold - warmap.cost[x1][y1]);
+	  
+	  /* We won't raze huts if we are barbarians. */
 	  if ((unknown > most_unknown || (unknown == most_unknown && myrand(2)))
 	      && !(is_barbarian(pplayer) && ptile->special & S_HUT)) {
 	    best_x = x1;
@@ -327,41 +349,59 @@
       }
     } whole_map_iterate_end;
 
+    /* a tile have unexplored territory adjectent, move there */
     if (most_unknown > 0) {
       punit->goto_dest_x = best_x;
       punit->goto_dest_y = best_y;
       handle_unit_activity_request(punit, ACTIVITY_GOTO);
       do_unit_goto(punit, GOTO_MOVE_ANY, 0);
+      
+      /* We can still move on.. */
       if (punit->moves_left) {
-	if (punit->x != best_x || punit->y != best_y) {
+	/* ..and we got into desired place. */
+	if (punit->x == best_x || punit->y == best_y) {
+	  return ai_manage_exploring(punit);
+	} else {
+	  /* Something wrong; what to do but go idle and return? */
 	  handle_unit_activity_request(punit, ACTIVITY_IDLE);
-	  return 1; /* Something wrong; what to do but return? */
-	} else
-	  return ai_manage_explorer(punit);
+	  return 1;
+	}
       } else {
 	return 1;
       }
     } /* no candidates; fall-through */
   }
 
-  /* BEGIN PART FOUR: maybe go to another continent */
+  /* We have nothing to explore, so we can go idle. */
   freelog(LOG_DEBUG, "%s's %s at (%d,%d) failed to explore.",
 	  pplayer->name, unit_type(punit)->name, punit->x, punit->y);
   handle_unit_activity_request(punit, ACTIVITY_IDLE);
+  
+  /* PART FOUR: Go home
+   * If we are AI controlled _military_ unit, we will return to
+   * our homecity, maybe even to another continent.
+   */
   if (pplayer->ai.control && is_military_unit(punit)) {
+    struct city *pcity;
+   
+    /* If we have a homecity.. */ 
     pcity = find_city_by_id(punit->homecity);
-    if (pcity && map_get_continent(pcity->x, pcity->y) == con)
-      ai_military_gohome(pplayer, punit);
-    else if (pcity) {
-      if (!find_boat(pplayer, &x, &y, 0)) /* Gilligan's Island */
-        punit->ai.ferryboat = -1;
+    if (pcity) {
+      if (map_get_continent(pcity->x, pcity->y) == continent)
+	ai_military_gohome(pplayer, punit);
       else {
-        punit->goto_dest_x = x;
-        punit->goto_dest_y = y;
-        do_unit_goto(punit, GOTO_MOVE_ANY, 0);
+        /* Sea travel */
+	if (!find_boat(pplayer, &x, &y, 0)) /* Gilligan's Island */
+	  punit->ai.ferryboat = -1; /* We are out of luck */
+	else {
+	  punit->goto_dest_x = x;
+	  punit->goto_dest_y = y;
+	  do_unit_goto(punit, GOTO_MOVE_ANY, 0);
+	}
       }
     }
   }
+
   return 0;
 }
 
@@ -1498,7 +1538,7 @@
             if (find_nearest_friendly_port(punit))
 	      do_unit_goto(punit, GOTO_MOVE_ANY, 0);
           } else {
-            ai_manage_explorer(punit); /* nothing else to do */
+            ai_manage_exploring(punit); /* nothing else to do */
             /* you can still have some moves left here, but barbarians should
                not sit helplessly, but advance towards nearest known enemy city */
 	    punit = find_unit_by_id(id);   /* unit might die while exploring */
@@ -1658,7 +1698,7 @@
       freelog(LOG_DEBUG, "Ferryboat %d@(%d,%d) stalling.",
 		    punit->id, punit->x, punit->y);
       if(is_barbarian(pplayer)) /* just in case */
-        ai_manage_explorer(punit);
+        ai_manage_exploring(punit);
     }
     return;
   }
@@ -1724,7 +1764,7 @@
     }
   }
   if (map_get_terrain(punit->x, punit->y) == T_OCEAN) /* thanks, Tony */
-    ai_manage_explorer(punit);
+    ai_manage_exploring(punit);
   return;
 }
 
@@ -1782,7 +1822,7 @@
     return; /* when you pillage, you have moves left, avoid later fortify */
     break;
   case AIUNIT_EXPLORE:
-    ai_manage_explorer(punit);
+    ai_manage_exploring(punit);
     break;
   default:
     abort();
@@ -1879,7 +1919,7 @@
     return;
   } else {
     if (!punit->moves_left) return; /* can't do anything with no moves */
-    ai_manage_explorer(punit); /* what else could this be? -- Syela */
+    ai_manage_exploring(punit); /* what else could this be? -- Syela */
     return;
   }
   /* should never get here */
diff -ru freeciv/ai/aiunit.h freeciv+pasky/ai/aiunit.h
--- freeciv/ai/aiunit.h	Wed Jan 10 19:50:45 2001
+++ freeciv+pasky/ai/aiunit.h	Sat Nov 24 21:05:01 2001
@@ -23,7 +23,7 @@
 int look_for_charge(struct player *pplayer, struct unit *punit,
                     struct unit **aunit, struct city **acity);
 
-int ai_manage_explorer(struct unit *punit);
+int ai_manage_exploring(struct unit *punit);
 
 int find_something_to_kill(struct player *pplayer, struct unit *punit, 
                             int *x, int *y);
diff -ru freeciv/server/unithand.c freeciv+pasky/server/unithand.c
--- freeciv/server/unithand.c	Tue Oct 30 11:37:17 2001
+++ freeciv+pasky/server/unithand.c	Sat Nov 24 21:06:15 2001
@@ -1256,8 +1256,8 @@
   case ACTIVITY_EXPLORE:
     if (punit->moves_left > 0) {
       int id = punit->id;
-      int more_to_explore = ai_manage_explorer(punit);
-      /* ai_manage_explorer sets the activity to idle, so we reset it */
+      int more_to_explore = ai_manage_exploring(punit);
+      /* ai_manage_exploring sets the activity to idle, so we reset it */
       if (more_to_explore && (punit = find_unit_by_id(id))) {
 	set_unit_activity(punit, ACTIVITY_EXPLORE);
 	send_unit_info(0, punit);
diff -ru freeciv/server/unittools.c freeciv+pasky/server/unittools.c
--- freeciv/server/unittools.c	Mon Nov 12 18:34:12 2001
+++ freeciv+pasky/server/unittools.c	Sat Nov 24 21:06:26 2001
@@ -803,7 +803,7 @@
   }
 
   if (activity == ACTIVITY_EXPLORE) {
-    int more_to_explore = ai_manage_explorer(punit);
+    int more_to_explore = ai_manage_exploring(punit);
     if (more_to_explore && player_find_unit_by_id(pplayer, id))
       handle_unit_activity_request(punit, ACTIVITY_EXPLORE);
     else