diff --git a/source/scriptinterface/ScriptInterface.cpp b/source/scriptinterface/ScriptInterface.cpp
index 4fe96cd2ef..8b35fbabd9 100644
--- a/source/scriptinterface/ScriptInterface.cpp
+++ b/source/scriptinterface/ScriptInterface.cpp
@@ -865,20 +865,21 @@ AutoGCRooter* ScriptInterface::ReplaceAutoGCRooter(AutoGCRooter* rooter)
 	return ret;
 }
 
-jsval ScriptInterface::CallConstructor(jsval ctor, uint argc, jsval argv)
+void ScriptInterface::CallConstructor(JS::HandleValue ctor, JS::AutoValueVector& argv, JS::MutableHandleValue out)
 {
 	JSAutoRequest rq(m->m_cx);
 	if (!ctor.isObject())
 	{
 		LOGERROR(L"CallConstructor: ctor is not an object");
-		return JS::UndefinedValue();
+		out.setNull();
+		return;
 	}
 
 	// Passing argc 0 and argv JSVAL_VOID causes a crash in mozjs24
-	if (argc == 0)
-		return JS::ObjectValue(*JS_New(m->m_cx, &ctor.toObject(), 0, NULL));
+	if (argv.length() == 0)
+		out.setObjectOrNull(JS_New(m->m_cx, &ctor.toObject(), 0, NULL));
 	else
-		return JS::ObjectValue(*JS_New(m->m_cx, &ctor.toObject(), argc, &argv));
+		out.setObjectOrNull(JS_New(m->m_cx, &ctor.toObject(), argv.length(), argv.begin()));
 }
 
 void ScriptInterface::DefineCustomObjectType(JSClass *clasp, JSNative constructor, uint minArgs, JSPropertySpec *ps, JSFunctionSpec *fs, JSPropertySpec *static_ps, JSFunctionSpec *static_fs)
diff --git a/source/scriptinterface/ScriptInterface.h b/source/scriptinterface/ScriptInterface.h
index ec6edb843c..a587e6b190 100644
--- a/source/scriptinterface/ScriptInterface.h
+++ b/source/scriptinterface/ScriptInterface.h
@@ -136,9 +136,11 @@ public:
 
 	/**
 	 * Call a constructor function, equivalent to JS "new ctor(arg)".
-	 * @return The new object; or JSVAL_VOID on failure, and logs an error message
+	 * @param ctor An object that can be used as constructor
+	 * @param argv Constructor arguments
+	 * @param out The new object; On error an error message gets logged and out is Null (out.isNull() == true).
 	 */
-	jsval CallConstructor(jsval ctor, uint argc, jsval argv);
+	void CallConstructor(JS::HandleValue ctor, JS::AutoValueVector& argv, JS::MutableHandleValue out);
 
 	/**
 	 * Call the named property on the given object, with void return type and 0 arguments
diff --git a/source/simulation2/components/CCmpAIManager.cpp b/source/simulation2/components/CCmpAIManager.cpp
index c281b76116..e1cf742738 100644
--- a/source/simulation2/components/CCmpAIManager.cpp
+++ b/source/simulation2/components/CCmpAIManager.cpp
@@ -114,7 +114,7 @@ private:
 			std::string constructor;
 			JS::RootedValue objectWithConstructor(cx); // object that should contain the constructor function
 			JS::RootedValue global(cx, m_ScriptInterface->GetGlobalObject());
-			CScriptVal ctor;
+			JS::RootedValue ctor(cx);
 			if (!m_ScriptInterface->HasProperty(metadata, "moduleName"))
 			{
 				objectWithConstructor.set(m_ScriptInterface->GetGlobalObject());
@@ -135,8 +135,8 @@ private:
 			}
 
 			// Get the constructor function from the loaded scripts
-			if (!m_ScriptInterface->GetProperty(objectWithConstructor, constructor.c_str(), ctor)
-				|| ctor.undefined())
+			if (!m_ScriptInterface->GetProperty(objectWithConstructor, constructor.c_str(), &ctor)
+				|| ctor.isNull())
 			{
 				LOGERROR(L"Failed to create AI player: %ls: can't find constructor '%hs'", path.string().c_str(), constructor.c_str());
 				return false;
@@ -144,7 +144,7 @@ private:
 
 			m_ScriptInterface->GetProperty(metadata, "useShared", m_UseSharedComponent);
 
-			CScriptVal obj;
+			JS::RootedValue obj(cx);
 
 			// Set up the data to pass as the constructor argument
 			JS::RootedValue settings(cx);
@@ -156,9 +156,9 @@ private:
 
 			JS::AutoValueVector argv(cx);
 			argv.append(settings.get());
-			obj = m_ScriptInterface->CallConstructor(ctor.get(), argv.length(), argv.handleAt(0));
+			m_ScriptInterface->CallConstructor(ctor, argv, &obj);
 
-			if (obj.undefined())
+			if (obj.isNull())
 			{
 				LOGERROR(L"Failed to create AI player: %ls: error calling constructor '%hs'", path.string().c_str(), constructor.c_str());
 				return false;
@@ -423,10 +423,12 @@ public:
 		
 		JS::AutoValueVector argv(cx);
 		argv.append(settings);
-		m_SharedAIObj = CScriptValRooted(cx, m_ScriptInterface->CallConstructor(ctor, argv.length(), argv.handleAt(0)));
-	
+		// TODO: Check if this temporary root can be removed after SpiderMonkey 31 upgrade 
+		JS::RootedValue tmpSharedAIObj(cx, m_SharedAIObj.get());
+		m_ScriptInterface->CallConstructor(ctor, argv, &tmpSharedAIObj);
+		m_SharedAIObj = CScriptValRooted(cx, tmpSharedAIObj);
 		
-		if (m_SharedAIObj.undefined())
+		if (tmpSharedAIObj.isNull())
 		{
 			LOGERROR(L"Failed to create shared AI component: %ls: error calling constructor '%hs'", path.string().c_str(), "SharedScript");
 			return false;
diff --git a/source/simulation2/system/ComponentManager.cpp b/source/simulation2/system/ComponentManager.cpp
index cb7ade20b4..7c7f267b4d 100644
--- a/source/simulation2/system/ComponentManager.cpp
+++ b/source/simulation2/system/ComponentManager.cpp
@@ -708,6 +708,9 @@ void CComponentManager::AddSystemComponents(bool skipScriptedComponents, bool sk
 
 IComponent* CComponentManager::ConstructComponent(CEntityHandle ent, ComponentTypeId cid)
 {
+	JSContext* cx = m_ScriptInterface.GetContext();
+	JSAutoRequest rq(cx);
+	
 	std::map<ComponentTypeId, ComponentType>::const_iterator it = m_ComponentTypesById.find(cid);
 	if (it == m_ComponentTypesById.end())
 	{
@@ -729,11 +732,14 @@ IComponent* CComponentManager::ConstructComponent(CEntityHandle ent, ComponentTy
 	std::map<entity_id_t, IComponent*>& emap2 = m_ComponentsByTypeId[cid];
 
 	// If this is a scripted component, construct the appropriate JS object first
-	jsval obj = JSVAL_NULL;
+	JS::RootedValue obj(cx);
+	// TODO: Check if this temporary root can be removed after SpiderMonkey 31 upgrade 
+	JS::RootedValue tmpCtor(cx, ct.ctor.get());
 	if (ct.type == CT_Script)
 	{
-		obj = m_ScriptInterface.CallConstructor(ct.ctor.get(), 0, JSVAL_VOID);
-		if (JSVAL_IS_VOID(obj))
+		JS::AutoValueVector argv(cx); // TODO: With SpiderMonkey 31, we can pass JS::HandleValueArray::empty()
+		m_ScriptInterface.CallConstructor(tmpCtor, argv, &obj);
+		if (obj.isNull())
 		{
 			LOGERROR(L"Script component constructor failed");
 			return NULL;