diff --git a/Global.h b/Global.h
index f9e25f3ff..3d777350e 100644
--- a/Global.h
+++ b/Global.h
@@ -676,6 +676,18 @@ namespace vstd
 		return v3;
 	}
 
+	template <typename Key, typename V>
+	bool containsMapping(const std::multimap<Key,V> & map, const std::pair<const Key,V> & mapping)
+	{
+		auto range = map.equal_range(mapping.first);
+		for(auto contained = range.first; contained != range.second; contained++)
+		{
+			if(mapping.second == contained->second)
+				return true;
+		}
+		return false;
+	}
+
 	using boost::math::round;
 }
 using vstd::operator-=;
diff --git a/config/skills.json b/config/skills.json
index d62bb0a0f..8107c6537 100644
--- a/config/skills.json
+++ b/config/skills.json
@@ -4,7 +4,7 @@
             "description" : "Hero generates 250 gold each day.",
             "effects" : [
                 {
-                    "subtype" : 13,
+                    "subtype" : "skill.estates",
                     "type" : "SECONDARY_SKILL_PREMY",
                     "val" : 250,
                     "valueType" : "BASE_NUMBER"
@@ -15,7 +15,7 @@
             "description" : "Hero generates 500 gold each day.",
             "effects" : [
                 {
-                    "subtype" : 13,
+                    "subtype" : "skill.estates",
                     "type" : "SECONDARY_SKILL_PREMY",
                     "val" : 500,
                     "valueType" : "BASE_NUMBER"
@@ -26,7 +26,7 @@
             "description" : "Hero generates 1000 gold each day.",
             "effects" : [
                 {
-                    "subtype" : 13,
+                    "subtype" : "skill.estates",
                     "type" : "SECONDARY_SKILL_PREMY",
                     "val" : 1000,
                     "valueType" : "BASE_NUMBER"
diff --git a/lib/CModHandler.cpp b/lib/CModHandler.cpp
index 3020235e1..bddf5ee23 100644
--- a/lib/CModHandler.cpp
+++ b/lib/CModHandler.cpp
@@ -204,8 +204,8 @@ void CIdentifierStorage::registerObject(std::string scope, std::string type, std
 	std::string fullID = type + '.' + name;
 	checkIdentifier(fullID);
 
-	auto mapping = std::make_pair(fullID, data);
-	if(!registeredObjects.contains(mapping))
+	std::pair<const std::string, ObjectData> mapping = std::make_pair(fullID, data);
+	if(!vstd::containsMapping(registeredObjects, mapping))
 	{
 		CLogger::getLogger(CLoggerDomain("identifier"))->traceStream() << "registered " << fullID << " as " << scope << ":" << identifier;
 		registeredObjects.insert(mapping);
diff --git a/lib/CModHandler.h b/lib/CModHandler.h
index 2655909cc..a3ed87b50 100644
--- a/lib/CModHandler.h
+++ b/lib/CModHandler.h
@@ -63,22 +63,7 @@ class CIdentifierStorage
 		}
 	};
 
-	class ObjectMap: public std::multimap<std::string, ObjectData>
-	{
-	public:
-		bool contains(const value_type & value) const
-		{
-			auto range = equal_range(value.first);
-			for(auto contained = range.first; contained != range.second; contained++)
-			{
-				if(value.second == contained->second)
-					return true;
-			}
-			return false;
-		}
-	};
-
-	ObjectMap registeredObjects;
+	std::multimap<std::string, ObjectData> registeredObjects;
 	std::vector<ObjectCallback> scheduledRequests;
 
 	ELoadingState state;