diff --git a/lib/OpenLayers/Layer.js b/lib/OpenLayers/Layer.js
index 8cea0f342e..261dfe50d6 100644
--- a/lib/OpenLayers/Layer.js
+++ b/lib/OpenLayers/Layer.js
@@ -435,6 +435,18 @@ OpenLayers.Layer.prototype = {
                        Math.round(1/resolution * (extent.top - lonlat.lat))
                        );    
     },
+    
+    /**
+     * Sets the opacity for the entire layer (all images)
+     * @param {Float} opacity
+     */
+    setOpacity: function(opacity) {
+        this.opacity = opacity;
+        for(var i=0; i<this.div.childNodes.length; ++i) {
+            var element = this.div.childNodes[i];
+            OpenLayers.Util.setOpacity(element, opacity);
+        }
+    },
 
     /** @final @type String */
     CLASS_NAME: "OpenLayers.Layer"
diff --git a/lib/OpenLayers/Tile/Image.js b/lib/OpenLayers/Tile/Image.js
index 021a6553b5..cf0e5deb51 100644
--- a/lib/OpenLayers/Tile/Image.js
+++ b/lib/OpenLayers/Tile/Image.js
@@ -102,6 +102,9 @@ OpenLayers.Tile.Image.prototype =
                                                       true);
         }
         this.layer.div.appendChild(this.imgDiv);
+        if(this.layer.opacity != null) {
+            OpenLayers.Util.setOpacity(this.imgDiv, this.layer.opacity);
+        }
     },
 
     /** @final @type String */
diff --git a/lib/OpenLayers/Util.js b/lib/OpenLayers/Util.js
index 5eabc6392b..76ebc80e2a 100644
--- a/lib/OpenLayers/Util.js
+++ b/lib/OpenLayers/Util.js
@@ -125,6 +125,19 @@ OpenLayers.Util.createImage = function(id, px, sz, imgURL, position, border,
     return image;
 };
 
+/**
+ * Set the opacity of a DOM Element
+ * Note that for this function to work in IE, elements must "have layout"
+ * according to:
+ * http://msdn.microsoft.com/workshop/author/dhtml/reference/properties/haslayout.asp
+ *
+ * @param {DOMElement} element Set the opacity on this DOM element
+ * @param {Float} opacity Opacity value (0.0 - 1.0)
+ */
+OpenLayers.Util.setOpacity = function(element, opacity) {
+    element.style.opacity = opacity;
+    element.style.filter = 'alpha(opacity=' + (opacity * 100) + ')';
+}
 
 OpenLayers.Util.onImageLoad = function() {
     this.style.backgroundColor = null;
diff --git a/tests/test_Layer_WMS.html b/tests/test_Layer_WMS.html
index 1c9085483e..cc133ea573 100644
--- a/tests/test_Layer_WMS.html
+++ b/tests/test_Layer_WMS.html
@@ -149,6 +149,31 @@
         t.eq(str, "http://octo.metacarta.com/cgi-bin/mapserv?LAYERS=basic&FORMAT=image/png&SERVICE=WMS&VERSION=1.1.1&REQUEST=GetMap&STYLES=&EXCEPTIONS=application/vnd.ogc.se_inimage", "getFullRequestString() by default does *not* add SRS value if projection is 'none'");
  
     }
+
+    function test_08_Layer_WMS_setOpacity (t) {
+        t.plan( 5 );
+
+        var map = new OpenLayers.Map('map');
+        map.projection = "xx";
+        tUrl = "http://octo.metacarta.com/cgi-bin/mapserv";
+        tParams = { layers: 'basic', 
+                   format: 'image/png'};
+        tOptions = { 'opacity': '0.5' };           
+        var tLayer = new OpenLayers.Layer.WMS(name, tUrl, tParams, tOptions);
+        map.addLayer(tLayer);
+        map.zoomToMaxExtent();
+        t.eq(tLayer.opacity, "0.5", "Opacity is set correctly");
+        t.eq(tLayer.div.firstChild.style.opacity, "0.5", "Opacity on tile is correct");
+        tLayer.setOpacity("0.6");
+        t.eq(tLayer.opacity, "0.6", "setOpacity works properly");
+        t.eq(tLayer.div.firstChild.style.opacity, "0.6", "Opacity on tile is changed correctly");
+        var pixel = new OpenLayers.Pixel(5,6);
+        var tile = tLayer.addTile(new OpenLayers.Bounds(1,2,3,4), pixel);
+        tile.draw();
+        t.eq(tile.imgDiv.style.opacity, "0.6", "Tile opacity is set correctly");
+
+    }    
+        
     
     function test_99_Layer_WMS_destroy (t) {