diff -Nur opensim-/OpenSim/Region/CoreModules/World/WorldMap/WorldMapModule.cs opensim/OpenSim/Region/CoreModules/World/WorldMap/WorldMapModule.cs
--- opensim-/OpenSim/Region/CoreModules/World/WorldMap/WorldMapModule.cs	2010-06-21 15:10:56.000000000 +0900
+++ opensim/OpenSim/Region/CoreModules/World/WorldMap/WorldMapModule.cs	2010-06-21 15:23:38.000000000 +0900
@@ -1006,7 +1006,9 @@
 
             m_log.Debug("[MAPTILE]: STORING MAPTILE IMAGE");
 
-            m_scene.RegionInfo.RegionSettings.TerrainImageID = UUID.Random();
+            UUID terrainImageID = UUID.Random();
+            m_scene.RegionInfo.RegionSettings.TerrainImageID = terrainImageID;
+            m_scene.RegionInfo.lastMapUUID = terrainImageID;
 
             AssetBase asset = new AssetBase(
                 m_scene.RegionInfo.RegionSettings.TerrainImageID,