diff --git a/AppKit/CPWindow/CPWindow.j b/AppKit/CPWindow/CPWindow.j
index 8a2f6e43f..d133d41d0 100644
--- a/AppKit/CPWindow/CPWindow.j
+++ b/AppKit/CPWindow/CPWindow.j
@@ -466,12 +466,26 @@ CPTexturedBackgroundWindowMask
     return _platformWindow;
 }
 
+/*!
+    Sets the platform window of the reciver.
+    This method will first close the reciever,
+    change the platform window, then reopen the window (if it was originally open).
+*/
 - (void)setPlatformWindow:(CPPlatformWindow)aPlatformWindow
 {
-    // FIXME: already visible.
+    var wasVisible = [self isVisible];
+
+    // we have to close it first, otherwise we get a DOM exception.
+    if (wasVisible)
+        [self close];
+
     _platformWindow = aPlatformWindow;
+
+    if (wasVisible)
+        [self orderFront:self];
 }
 
+
 /*!
     @ignore
 */
diff --git a/Foundation/CPIndexPath.j b/Foundation/CPIndexPath.j
index a7ee64137..720d859c8 100644
--- a/Foundation/CPIndexPath.j
+++ b/Foundation/CPIndexPath.j
@@ -83,6 +83,16 @@
     return [_indexes objectAtIndex:position];
 }
 
+- (void)setIndexes:(CPArray)theIndexes
+{
+    _indexes = [theIndexes copy];
+}
+
+- (CPArray)indexes
+{
+    return [_indexes copy];
+}
+
 #pragma mark -
 #pragma mark Modification
 
@@ -93,7 +103,7 @@
 
 - (CPIndexPath)indexPathByRemovingLastIndex
 {
-    return [CPIndexPath indexPathWithIndexes:_indexes length:[self length]];
+    return [CPIndexPath indexPathWithIndexes:_indexes length:[self length] - 1];
 }
 
 #pragma mark -
diff --git a/Tests/Foundation/CPIndexPathTest.j b/Tests/Foundation/CPIndexPathTest.j
index 4c85f9d30..49bc5a851 100644
--- a/Tests/Foundation/CPIndexPathTest.j
+++ b/Tests/Foundation/CPIndexPathTest.j
@@ -35,11 +35,23 @@
 
 - (void)testIndexPathByRemovingLastIndex
 {
-    var ip = [indexPath indexes];
-    [ip removeLastObject];
+    // Keep removing indexes until the indexPath is empty
+    while ([indexPath length] > 0)
+    {
+        var expectedIndexes = [[indexPath indexes] copy];
+        [expectedIndexes removeObject:[expectedIndexes lastObject]];
 
-    [self assert:[CPIndexPath indexPathWithIndexes:ip]
-          equals:[indexPath indexPathByRemovingLastIndex]];
+        indexPath = [indexPath indexPathByRemovingLastIndex];
+        [self assert:[CPIndexPath indexPathWithIndexes:expectedIndexes] equals:indexPath];
+    }
+}
+
+- (void)testIndexes
+{
+    var newIndexes = [indexPath indexes];
+    [newIndexes removeObjectAtIndex:0];
+
+    [self assert:[indexPath indexes] notEqual:newIndexes];
 }
 
 - (void)testCompareThrowsOnNil