diff --git a/source/src/clients2c.cpp b/source/src/clients2c.cpp
index 33658dba..9bbec2f0 100644
--- a/source/src/clients2c.cpp
+++ b/source/src/clients2c.cpp
@@ -498,6 +498,16 @@ void parsemessages(int cn, playerent *d, ucharbuf &p)
                 break;
             }
 
+            case SV_NEWMAP:
+            {
+                int size = getint(p);
+                if(size>=0) empty_world(size, true);
+                else empty_world(-1, true);
+                if(d && d!=player1)
+                    conoutf(size>=0 ? "%s started a new map of size %d" : "%s enlarged the map to size %d", colorname(d), sfactor);
+                break;
+            }
+
             case SV_EDITENT:            // coop edit of ent
             {
                 uint i = getint(p);
diff --git a/source/src/protocol.cpp b/source/src/protocol.cpp
index a262d884..8120be85 100644
--- a/source/src/protocol.cpp
+++ b/source/src/protocol.cpp
@@ -139,7 +139,7 @@ char msgsizesl[] =               // size inclusive message token, 0 for variable
     SV_TIMEUP, 2, SV_EDITENT, 10, SV_MAPRELOAD, 2, SV_NEXTMAP, 0, SV_ITEMACC, 2,
     SV_MAPCHANGE, 0, SV_ITEMSPAWN, 2, SV_ITEMPICKUP, 2,
     SV_PING, 2, SV_PONG, 2, SV_CLIENTPING, 2, SV_GAMEMODE, 2,
-    SV_EDITMODE, 2, SV_EDITH, 7, SV_EDITT, 7, SV_EDITS, 6, SV_EDITD, 6, SV_EDITE, 6,
+    SV_EDITMODE, 2, SV_EDITH, 7, SV_EDITT, 7, SV_EDITS, 6, SV_EDITD, 6, SV_EDITE, 6, SV_NEWMAP, 2,
     SV_SENDMAP, 0, SV_RECVMAP, 1, SV_SERVMSG, 0, SV_ITEMLIST, 0, SV_WEAPCHANGE, 2, SV_PRIMARYWEAP, 2,
     SV_MODELSKIN, 2,
     SV_FLAGACTION, 3, SV_FLAGINFO, 0, SV_FLAGMSG, 0, SV_FLAGCNT, 3,
diff --git a/source/src/protocol.h b/source/src/protocol.h
index 2324c4a4..e55a5ab1 100644
--- a/source/src/protocol.h
+++ b/source/src/protocol.h
@@ -21,7 +21,7 @@ enum
     SV_TIMEUP, SV_EDITENT, SV_MAPRELOAD, SV_NEXTMAP, SV_ITEMACC,
     SV_MAPCHANGE, SV_ITEMSPAWN, SV_ITEMPICKUP,
     SV_PING, SV_PONG, SV_CLIENTPING, SV_GAMEMODE,
-    SV_EDITMODE, SV_EDITH, SV_EDITT, SV_EDITS, SV_EDITD, SV_EDITE,
+    SV_EDITMODE, SV_EDITH, SV_EDITT, SV_EDITS, SV_EDITD, SV_EDITE, SV_NEWMAP,
     SV_SENDMAP, SV_RECVMAP, SV_SERVMSG, SV_ITEMLIST, SV_WEAPCHANGE, SV_PRIMARYWEAP,
     SV_MODELSKIN,
     SV_FLAGACTION, SV_FLAGINFO, SV_FLAGMSG, SV_FLAGCNT,
@@ -51,7 +51,7 @@ const static char *messagenames[] =
     "SV_TIMEUP", "SV_EDITENT", "SV_MAPRELOAD", "SV_NEXTMAP", "SV_ITEMACC",
     "SV_MAPCHANGE", "SV_ITEMSPAWN", "SV_ITEMPICKUP",
     "SV_PING", "SV_PONG", "SV_CLIENTPING", "SV_GAMEMODE",
-    "SV_EDITMODE", "SV_EDITH", "SV_EDITT", "SV_EDITS", "SV_EDITD", "SV_EDITE",
+    "SV_EDITMODE", "SV_EDITH", "SV_EDITT", "SV_EDITS", "SV_EDITD", "SV_EDITE", "SV_NEWMAP", 
     "SV_SENDMAP", "SV_RECVMAP", "SV_SERVMSG", "SV_ITEMLIST", "SV_WEAPCHANGE", "SV_PRIMARYWEAP",
     "SV_MODELSKIN",
     "SV_FLAGACTION", "SV_FLAGINFO", "SV_FLAGMSG", "SV_FLAGCNT",
diff --git a/source/src/protos.h b/source/src/protos.h
index 3fda54ac..5b5779eb 100644
--- a/source/src/protos.h
+++ b/source/src/protos.h
@@ -373,7 +373,7 @@ extern void consolescores();
 
 // world
 extern void setupworld(int factor);
-extern void empty_world(int factor, bool force);
+extern bool empty_world(int factor, bool force);
 extern void remip(const block &b, int level = 0);
 extern void remipmore(const block &b, int level = 0);
 extern int closestent();
diff --git a/source/src/server.cpp b/source/src/server.cpp
index 77af6264..1400a595 100644
--- a/source/src/server.cpp
+++ b/source/src/server.cpp
@@ -2325,7 +2325,7 @@ int checktype(int type, client *cl)
 {
     if(cl && cl->type==ST_LOCAL) return type;
     // only allow edit messages in coop-edit mode
-    static int edittypes[] = { SV_EDITENT, SV_EDITH, SV_EDITT, SV_EDITS, SV_EDITD, SV_EDITE };
+    static int edittypes[] = { SV_EDITENT, SV_EDITH, SV_EDITT, SV_EDITS, SV_EDITD, SV_EDITE, SV_NEWMAP };
     if(cl && smode!=1) loopi(sizeof(edittypes)/sizeof(int)) if(type == edittypes[i]) return -1;
     // server only messages
     static int servtypes[] = { SV_INITS2C, SV_MAPRELOAD, SV_SERVMSG, SV_GIBDAMAGE, SV_DAMAGE,
diff --git a/source/src/world.cpp b/source/src/world.cpp
index 8276d75e..39ef231b 100644
--- a/source/src/world.cpp
+++ b/source/src/world.cpp
@@ -286,9 +286,9 @@ void setupworld(int factor)
     loopi(LARGEST_FACTOR*2) { wmip[i] = w; w += cubicsize>>(i*2); }
 }
 
-void empty_world(int factor, bool force)    // main empty world creation routine, if passed factor -1 will enlarge old world by 1
+bool empty_world(int factor, bool force)    // main empty world creation routine, if passed factor -1 will enlarge old world by 1
 {
-    if(!force && noteditmode()) return; 
+    if(!force && noteditmode()) return false; 
     sqr *oldworld = world;
     bool copy = false;
     if(oldworld && factor<0) { factor = sfactor+1; copy = true; }
@@ -360,10 +360,11 @@ void empty_world(int factor, bool force)    // main empty world creation routine
         findplayerstart(player1, true);
         startmap("");
     }
+    return true;
 }
 
-void mapenlarge()  { empty_world(-1, false); }
-void newmap(int i) { empty_world(i, false); }
+void mapenlarge()  { if(empty_world(-1, false)) addmsg(SV_NEWMAP, "ri", -1); }
+void newmap(int i) { if(empty_world(i, false)) addmsg(SV_NEWMAP, "ri", max(i, 0)); }
 
 COMMAND(mapenlarge, ARG_NONE);
 COMMAND(newmap, ARG_1INT);