diff --git a/CHANGELOG b/CHANGELOG
index d95b16a..ce3d9bf 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,5 +1,7 @@
 *SVN*
 
+* Make Object.isArray correctly identify arrays created in another frame. Closes #10374. [pointy, Dean Edwards, Andrew Dupont, Tobie Langel]
+
 * Fixed issue where Element#match failed on attribute selectors with single or double quotes. Closes #10067. [Cezary Okupski, Andrew Dupont]
 
 * Add tests for Element#match.  [Tobie Langel]
diff --git a/src/base.js b/src/base.js
index 9884aaf..2d75f32 100644
--- a/src/base.js
+++ b/src/base.js
@@ -132,7 +132,8 @@ Object.extend(Object, {
   },
   
   isArray: function(object) {
-    return object && object.constructor === Array;
+    return object != null && typeof object == "object" &&
+      'splice' in object && 'join' in object;
   },
   
   isHash: function(object) {
diff --git a/test/unit/base.html b/test/unit/base.html
index 9828428..51c8e95 100644
--- a/test/unit/base.html
+++ b/test/unit/base.html
@@ -22,7 +22,12 @@
 
 <!-- Log output -->
 <div id="testlog"> </div>
-<div id="test"></div> 
+<div id="test"></div>
+<ul id="list">
+  <li></li>
+  <li></li>
+  <li></li>
+</ul>
 <!-- Tests follow -->
 <script type="text/javascript" language="javascript" charset="utf-8">
 // <![CDATA[
@@ -311,6 +316,16 @@
       assert(Object.isArray([0]));
       assert(Object.isArray([0, 1]));
       assert(!Object.isArray({}));
+      assert(!Object.isArray($('list').childNodes));
+      assert(!Object.isArray());
+      assert(!Object.isArray(''));
+      assert(!Object.isArray('foo'));
+      assert(!Object.isArray(0));
+      assert(!Object.isArray(1));
+      assert(!Object.isArray(null));
+      assert(!Object.isArray(true));
+      assert(!Object.isArray(false));
+      assert(!Object.isArray(undefined));
     }},
     
     testObjectIsHash: function() { with(this) {