diff --git a/src/g_doomedmap.cpp b/src/g_doomedmap.cpp
index 131ddd076..c9deb7256 100644
--- a/src/g_doomedmap.cpp
+++ b/src/g_doomedmap.cpp
@@ -80,7 +80,8 @@ const char *SpecialMapthingNames[] = {
 struct MapinfoEdMapItem
 {
 	FName classname;	// DECORATE is read after MAPINFO so we do not have the actual classes available here yet.
-	int special;
+	short special;
+	bool argsdefined;
 	int args[5];
 	// These are for error reporting. We must store the file information because it's no longer available when these items get resolved.
 	FString filename;
@@ -180,14 +181,15 @@ void FMapInfoParser::ParseDoomEdNums()
 				editem.special = -1;
 			}
 			memset(editem.args, 0, sizeof(editem.args));
+			editem.argsdefined = false;
 
 			int minargs = 0;
 			int maxargs = 5;
 			FString specialname;
 			if (sc.CheckString(","))
 			{
-				// todo: parse a special or args
-				if (editem.special < 0) editem.special = 0;	// mark args as used - if this is done we need to prevent assignment of map args in P_SpawnMapThing.
+				editem.argsdefined = true; // mark args as used - if this is done we need to prevent assignment of map args in P_SpawnMapThing.
+				if (editem.special < 0) editem.special = 0;
 				if (!sc.CheckNumber())
 				{
 					sc.MustGetString();
@@ -264,6 +266,7 @@ void InitActorNumsFromMapinfo()
 		FDoomEdEntry ent;
 		ent.Type = cls;
 		ent.Special = pair->Value.special;
+		ent.ArgsDefined = pair->Value.argsdefined;
 		memcpy(ent.Args, pair->Value.args, sizeof(ent.Args));
 		DoomEdMap.Insert(pair->Key, ent);
 	}
diff --git a/src/info.h b/src/info.h
index 8eed93e48..bdbb69940 100644
--- a/src/info.h
+++ b/src/info.h
@@ -282,7 +282,8 @@ struct FActorInfo
 struct FDoomEdEntry
 {
 	const PClass *Type;
-	int Special;
+	short Special;
+	bool ArgsDefined;
 	int Args[5];
 };
 
diff --git a/src/p_mobj.cpp b/src/p_mobj.cpp
index e3317e1a2..2571413c8 100644
--- a/src/p_mobj.cpp
+++ b/src/p_mobj.cpp
@@ -4617,9 +4617,9 @@ AActor *P_SpawnMapThing (FMapThing *mthing, int position)
 	}
 
 	// copy args to mapthing so that we have them in one place for the rest of this function	
-	if (mentry->Type != NULL && mentry->Special >= 0)
+	if (mentry->ArgsDefined)
 	{
-		mthing->special = mentry->Special;
+		if (mentry->Type!= NULL) mthing->special = mentry->Special;
 		memcpy(mthing->args, mentry->Args, sizeof(mthing->args));
 	}