diff --git a/OpenSim/Framework/RegionInfo.cs b/OpenSim/Framework/RegionInfo.cs
index ce14b58a3e..7ac94a04e7 100644
--- a/OpenSim/Framework/RegionInfo.cs
+++ b/OpenSim/Framework/RegionInfo.cs
@@ -147,8 +147,29 @@ namespace OpenSim.Framework
         public uint WorldLocX = 0;
         public uint WorldLocY = 0;
         public uint WorldLocZ = 0;
+
+        /// <summary>
+        /// X dimension of the region.
+        /// </summary>
+        /// <remarks>
+        /// If this is a varregion then the default size set here will be replaced when we load the region config.
+        /// </remarks>
         public uint RegionSizeX = Constants.RegionSize;
+
+        /// <summary>
+        /// X dimension of the region.
+        /// </summary>
+        /// <remarks>
+        /// If this is a varregion then the default size set here will be replaced when we load the region config.
+        /// </remarks>
         public uint RegionSizeY = Constants.RegionSize;
+
+        /// <summary>
+        /// Z dimension of the region.
+        /// </summary>
+        /// <remarks>
+        /// XXX: Unknown if this accounts for regions with negative Z.
+        /// </remarks>
         public uint RegionSizeZ = Constants.RegionHeight;
 
         private Dictionary<String, String> m_extraSettings = new Dictionary<string, string>();
diff --git a/OpenSim/Region/CoreModules/World/WorldMap/WorldMapModule.cs b/OpenSim/Region/CoreModules/World/WorldMap/WorldMapModule.cs
index b98afbcb3d..e4977cfdc0 100644
--- a/OpenSim/Region/CoreModules/World/WorldMap/WorldMapModule.cs
+++ b/OpenSim/Region/CoreModules/World/WorldMap/WorldMapModule.cs
@@ -1578,12 +1578,20 @@ namespace OpenSim.Region.CoreModules.World.WorldMap
 
         private Byte[] GenerateOverlay()
         {
-            using (Bitmap overlay = new Bitmap(256, 256))
+            // These need to be ints for bitmap generation
+            int regionSizeX = (int)m_scene.RegionInfo.RegionSizeX;
+            int regionSizeY = (int)m_scene.RegionInfo.RegionSizeY;
+
+            int landTileSize = LandManagementModule.LandUnit;
+            int regionLandTilesX = regionSizeX / landTileSize;
+            int regionLandTilesY = regionSizeY / landTileSize;
+
+            using (Bitmap overlay = new Bitmap(regionSizeX, regionSizeY))
             {
-                bool[,] saleBitmap = new bool[64, 64];
-                for (int x = 0 ; x < 64 ; x++)
+                bool[,] saleBitmap = new bool[regionLandTilesX, regionLandTilesY];
+                for (int x = 0; x < regionLandTilesX; x++)
                 {
-                    for (int y = 0 ; y < 64 ; y++)
+                    for (int y = 0; y < regionLandTilesY; y++)
                         saleBitmap[x, y] = false;
                 }
 
@@ -1596,8 +1604,7 @@ namespace OpenSim.Region.CoreModules.World.WorldMap
                 using (Graphics g = Graphics.FromImage(overlay))
                 {
                     using (SolidBrush transparent = new SolidBrush(background))
-                        g.FillRectangle(transparent, 0, 0, 256, 256);
-
+                        g.FillRectangle(transparent, 0, 0, regionSizeX, regionSizeY);
 
                     foreach (ILandObject land in parcels)
                     {
@@ -1620,12 +1627,16 @@ namespace OpenSim.Region.CoreModules.World.WorldMap
 
                     using (SolidBrush yellow = new SolidBrush(Color.FromArgb(255, 249, 223, 9)))
                     {
-                        for (int x = 0 ; x < 64 ; x++)
+                        for (int x = 0 ; x < regionLandTilesX ; x++)
                         {
-                            for (int y = 0 ; y < 64 ; y++)
+                            for (int y = 0 ; y < regionLandTilesY ; y++)
                             {
                                 if (saleBitmap[x, y])
-                                    g.FillRectangle(yellow, x * 4, 252 - (y * 4), 4, 4);
+                                    g.FillRectangle(
+                                        yellow, x * landTileSize, 
+                                        regionSizeX - landTileSize - (y * landTileSize), 
+                                        landTileSize, 
+                                        landTileSize);
                             }
                         }
                     }
@@ -1654,4 +1665,4 @@ namespace OpenSim.Region.CoreModules.World.WorldMap
         public uint itemtype;
         public ulong regionhandle;
     }
-}
+}
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