Paul Prescod <paul@prescod.net>:
Correct the chaining between siblings.
diff --git a/Lib/xml/dom/minidom.py b/Lib/xml/dom/minidom.py
index 3ed7236..6dc3a52 100644
--- a/Lib/xml/dom/minidom.py
+++ b/Lib/xml/dom/minidom.py
@@ -102,6 +102,13 @@
             newChild.parentNode = self
 
     def appendChild(self, node):
+        if self.childNodes:
+            last = self.lastChild
+            node.previousSibling = last
+            last.nextSibling = node
+        else:
+            node.previousSibling = None
+        node.nextSibling = None
         self.childNodes.append(node)
         return node