diff --git a/lib/OpenLayers/Handler/MouseWheel.js b/lib/OpenLayers/Handler/MouseWheel.js
index e75ce0a415..6bfd513dae 100644
--- a/lib/OpenLayers/Handler/MouseWheel.js
+++ b/lib/OpenLayers/Handler/MouseWheel.js
@@ -114,12 +114,13 @@ OpenLayers.Handler.MouseWheel = OpenLayers.Class(OpenLayers.Handler, {
 
             if (!overScrollableDiv) {
                 try {
+                    var overflow;
                     if (elem.currentStyle) {
                         overflow = elem.currentStyle["overflow"];
                     } else {
                         var style = 
                             document.defaultView.getComputedStyle(elem, null);
-                        var overflow = style.getPropertyValue("overflow");
+                        overflow = style.getPropertyValue("overflow");
                     }
                     overScrollableDiv = ( overflow && 
                         (overflow == "auto") || (overflow == "scroll") );