diff --git a/layout/base/tests/chrome/test_leaf_layers_partition_browser_window.xul b/layout/base/tests/chrome/test_leaf_layers_partition_browser_window.xul
index f018b3c6ef7f..79e684001f1e 100644
--- a/layout/base/tests/chrome/test_leaf_layers_partition_browser_window.xul
+++ b/layout/base/tests/chrome/test_leaf_layers_partition_browser_window.xul
@@ -17,6 +17,15 @@
   <![CDATA[
     SimpleTest.waitForExplicitFinish();
 
+    // Bug 640889 - the test doesn't like seeing the WinXP resizer.
+    var version = Components.classes["@mozilla.org/system-info;1"]
+                            .getService(Components.interfaces.nsIPropertyBag2)
+                            .getProperty("version");
+    if (navigator.platform.indexOf("Win") == 0 && parseFloat(version) < 6.0) {
+      todo(false, "Bug 640889 - the test doesn't like seeing the WinXP resizer.");
+      SimpleTest.finish();
+    } else {
+
     // Run the test in a separate window so we get a clean browser window.
     window.open("data:text/html,<html style='overflow:scroll'><script>opener.doTest(window);</script>",
                 "", "scrollbars=yes,toolbar,menubar,width=500,height=500");
@@ -46,6 +55,7 @@
 
       SimpleTest.executeSoon(nextStep);
     }
+    }
   ]]>
   </script>
 </window>
