diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..e167ff3
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,2 @@
+*.py[co]
+*.egg-info/
\ No newline at end of file
diff --git a/treeadmin/admin.py b/treeadmin/admin.py
index 1b31089..0782745 100644
--- a/treeadmin/admin.py
+++ b/treeadmin/admin.py
@@ -3,9 +3,13 @@
 from django.contrib.admin.views import main
 from django.db.models import Q
 from django.http import HttpResponse, HttpResponseBadRequest, HttpResponseForbidden, HttpResponseNotFound, HttpResponseServerError
-from django.utils import simplejson
+try:
+    import django.utils.simplejson
+except:
+    import json as simplejson
 from django.utils.safestring import mark_safe
 from django.utils.translation import ugettext_lazy as _, ugettext
+from django import VERSION as django_version
 
 from mptt.exceptions import InvalidMove
 
@@ -48,7 +52,9 @@ def _build_tree_structure(cls):
     else:
         mptt_opts = cls._meta
 
-    for p_id, parent_id in cls.objects.order_by(mptt_opts.tree_id_attr, mptt_opts.left_attr).values_list("pk", "%s_id" % mptt_opts.parent_attr):
+    values_list = [tuple(dct.values()) for dct in cls.objects.order_by(mptt_opts.tree_id_attr, mptt_opts.left_attr).values("pk", "%s_id" % mptt_opts.parent_attr)]
+
+    for p_id, parent_id in values_list:
         all_nodes[p_id] = []
 
         if parent_id:
@@ -127,9 +133,22 @@ def __init__(self, request, *args, **kwargs):
         self.user = request.user
         super(ChangeList, self).__init__(request, *args, **kwargs)
 
-    def get_query_set(self, *args, **kwargs):
+    def get_queryset(self, *args, **kwargs):
         mptt_opts = self.model._mptt_meta
-        return super(ChangeList, self).get_query_set(*args, **kwargs).order_by(mptt_opts.tree_id_attr, mptt_opts.left_attr)
+        get_qs = getattr(super(ChangeList, self), 'get_queryset', super(ChangeList, self).get_query_set)
+        return get_qs(*args, **kwargs).order_by(mptt_opts.tree_id_attr, mptt_opts.left_attr)
+
+    if django_version < (1, 6):
+        get_query_set = get_queryset
+
+        @property
+        def query_set(self):
+            return self.queryset
+
+        @query_set.setter
+        def query_set(self, qs):
+            self.queryset = qs
+
 
     def get_results(self, request):
         mptt_opts = self.model._mptt_meta
@@ -139,9 +158,9 @@ def get_results(self, request):
                 mptt_opts.left_attr + '__lte': lft,
                 mptt_opts.right_attr + '__gte': rght,
             }) for lft, rght, tree_id in \
-                self.query_set.values_list(mptt_opts.left_attr, mptt_opts.right_attr, mptt_opts.tree_id_attr)]
+                self.queryset.values_list(mptt_opts.left_attr, mptt_opts.right_attr, mptt_opts.tree_id_attr)]
             if clauses:
-                self.query_set = self.model._default_manager.filter(reduce(lambda p, q: p|q, clauses))
+                self.queryset = self.model._default_manager.filter(reduce(lambda p, q: p|q, clauses))
 
         super(ChangeList, self).get_results(request)