diff --git a/lib/OpenLayers/Map.js b/lib/OpenLayers/Map.js
index fae32f8474..61144e05dc 100644
--- a/lib/OpenLayers/Map.js
+++ b/lib/OpenLayers/Map.js
@@ -732,6 +732,7 @@ OpenLayers.Map = OpenLayers.Class({
             }
         }    
         
+        layer.div.className = "olLayerDiv";
         layer.div.style.overflow = "";
         this.setLayerZIndex(layer, this.layers.length);
 
diff --git a/theme/default/style.css b/theme/default/style.css
index 061619ffa9..a0e92093e4 100644
--- a/theme/default/style.css
+++ b/theme/default/style.css
@@ -1,4 +1,4 @@
-div.olMapViewport {
+div.olLayerDiv {
    -moz-user-select: none 
 }