diff --git a/lib/OpenLayers/Layer/HTTPRequest.js b/lib/OpenLayers/Layer/HTTPRequest.js
index 8f939f7b40..0ae44bcbc1 100644
--- a/lib/OpenLayers/Layer/HTTPRequest.js
+++ b/lib/OpenLayers/Layer/HTTPRequest.js
@@ -143,9 +143,10 @@ OpenLayers.Layer.HTTPRequest = OpenLayers.Class(OpenLayers.Layer, {
      */
     redraw: function(force) { 
         if (force) {
-            this.params["_olSalt"] = Math.random();
+            this.mergeNewParams({"_olSalt": Math.random()});
+        } else {
+            return OpenLayers.Layer.prototype.redraw.call(this);
         }
-        return OpenLayers.Layer.prototype.redraw.call(this);
     },
     
     /**