diff --git a/source/graphics/MapGenerator.cpp b/source/graphics/MapGenerator.cpp
index 1499eee03c..bda965c6cb 100644
--- a/source/graphics/MapGenerator.cpp
+++ b/source/graphics/MapGenerator.cpp
@@ -1,4 +1,4 @@
-/* Copyright (C) 2015 Wildfire Games.
+/* Copyright (C) 2017 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -118,12 +118,10 @@ bool CMapGeneratorWorker::Run()
 	}
 
 	// Init RNG seed
-	u32 seed;
-	if (!m_ScriptInterface->GetProperty(settingsVal, "Seed", seed))
-	{	// No seed specified
+	u32 seed = 0;
+	if (!m_ScriptInterface->HasProperty(settingsVal, "Seed") ||
+	    !m_ScriptInterface->GetProperty(settingsVal, "Seed", seed))
 		LOGWARNING("CMapGeneratorWorker::Run: No seed value specified - using 0");
-		seed = 0;
-	}
 
 	m_MapGenRNG.seed(seed);
 
diff --git a/source/simulation2/Simulation2.cpp b/source/simulation2/Simulation2.cpp
index fef97bf016..a52a4c8ce6 100644
--- a/source/simulation2/Simulation2.cpp
+++ b/source/simulation2/Simulation2.cpp
@@ -1,4 +1,4 @@
-/* Copyright (C) 2016 Wildfire Games.
+/* Copyright (C) 2017 Wildfire Games.
  * This file is part of 0 A.D.
  *
  * 0 A.D. is free software: you can redistribute it and/or modify
@@ -794,7 +794,8 @@ void CSimulation2::SetMapSettings(JS::HandleValue settings)
 	m->m_MapSettings = settings;
 
 	u32 seed = 0;
-	if (!m->m_ComponentManager.GetScriptInterface().GetProperty(m->m_MapSettings, "Seed", seed))
+	if (!m->m_ComponentManager.GetScriptInterface().HasProperty(m->m_MapSettings, "Seed") ||
+	    !m->m_ComponentManager.GetScriptInterface().GetProperty(m->m_MapSettings, "Seed", seed))
 		LOGWARNING("CSimulation2::SetInitAttributes: No seed value specified - using %d", seed);
 
 	m->m_ComponentManager.SetRNGSeed(seed);