diff --git a/lib/OpenLayers/Util.js b/lib/OpenLayers/Util.js
index 611ea839a8..4cf91d524b 100644
--- a/lib/OpenLayers/Util.js
+++ b/lib/OpenLayers/Util.js
@@ -339,7 +339,7 @@ OpenLayers.Util.onImageLoad = function() {
     //
     if (!this.viewRequestID ||
         (this.map && this.viewRequestID == this.map.viewRequestID)) { 
-        this.style.backgroundColor = null;
+        this.style.backgroundColor ="transparent";
         this.style.display = "";  
     }
 };